From fe249d7892913ee96564ff21ee1e3136dd95533c Mon Sep 17 00:00:00 2001
From: phlangiee <174984579+phlangiee@users.noreply.github.com>
Date: Tue, 18 Nov 2025 02:10:14 -0800
Subject: [PATCH 01/16] Get the judge to team pairings from the previous round

---
 .../judgeToTeam/getJudgeToTeamPairings.ts     | 26 +++++++++++++++++++
 .../_utils/matching/judgesToTeamsAlgorithm.ts | 13 +++++++++-
 2 files changed, 38 insertions(+), 1 deletion(-)
 create mode 100644 app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts

diff --git a/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts b/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
new file mode 100644
index 00000000..d70c1f83
--- /dev/null
+++ b/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
@@ -0,0 +1,26 @@
+import JudgeToTeam from '@typeDefs/judgeToTeam';
+import { getDatabase } from '@utils/mongodb/mongoClient.mjs';
+import parseAndReplace from '@utils/request/parseAndReplace';
+import { HttpError } from '@utils/response/Errors';
+import { ObjectId } from 'mongodb';
+import Submission from '@typeDefs/submission';
+
+export const GetJudgeToTeamPairings = async () => {
+    try {
+        const db = await getDatabase();
+        const submissions = await db
+            .collection('submissions') 
+            .find()
+            .toArray();
+        
+        const pairings = submissions.map((submission: Submission) => ({ 
+            judge_id: submission.judge_id, 
+            team_id: submission.team_id
+        }));
+        // erm im not sure if i did this right??
+
+        return { ok: true, body: pairings as JudgeToTeam[], error: null}; 
+        const error = e as HttpError;
+        return { ok: false, body: null, error: error.message };
+    }
+}
\ No newline at end of file
diff --git a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
index ddad3c8f..31ecc236 100644
--- a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
+++ b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
@@ -6,6 +6,7 @@ import { optedHDTracks, nonHDTracks } from '@data/tracks';
 
 import { GetManyUsers } from '@datalib/users/getUser';
 import { GetManyTeams } from '@datalib/teams/getTeam';
+import { GetJudgeToTeamPairings } from '@datalib/judgeToTeam/getJudgeToTeamPairings';
 
 interface Judge {
   user: User;
@@ -66,7 +67,7 @@ export default async function matchAllTeams(options?: { alpha?: number }) {
   const teamMatchQualities: { [teamId: string]: number[] } = {};
   const teamJudgeDomainTypes: { [teamId: string]: string[] } = {};
 
-  const rounds = 3;
+  const rounds = 2;
   const ALPHA = options?.alpha ?? 4;
   // Fetch all checked in judges.
   const judgesResponse = await GetManyUsers({
@@ -157,6 +158,16 @@ export default async function matchAllTeams(options?: { alpha?: number }) {
       .filter((team) => team.tracks.length < rounds)
       .map((team) => [team._id ?? '', rounds - team.tracks.length])
   );
+
+  // Get previous pairings
+  const previousPairings = await GetJudgeToTeamPairings();
+  if (previousPairings.ok) {
+    const isSecondRound = previousPairings.body.length !== 0 ? true : false;
+  } else {
+    console.log(previousPairings.error);
+    const isSecondRound = false; 
+  }
+
   // Main loop: process each team for each round.
   for (let domainIndex = 0; domainIndex < rounds; domainIndex++) {
     for (const team of modifiedTeams) {

From ff8dfd8495f7c56eab6f96f83d2924b4699115c6 Mon Sep 17 00:00:00 2001
From: phlangiee <174984579+phlangiee@users.noreply.github.com>
Date: Tue, 18 Nov 2025 02:33:16 -0800
Subject: [PATCH 02/16] Oppsie i accidentiy deleted catch

---
 app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts b/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
index d70c1f83..cf8288a1 100644
--- a/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
+++ b/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
@@ -19,8 +19,10 @@ export const GetJudgeToTeamPairings = async () => {
         }));
         // erm im not sure if i did this right??
 
-        return { ok: true, body: pairings as JudgeToTeam[], error: null}; 
+        return { ok: true, body: pairings as JudgeToTeam[], error: null}; // um not sure if the format in the db is the exact same as the judgetoteam??
+    } catch (e) {
         const error = e as HttpError;
         return { ok: false, body: null, error: error.message };
     }
-}
\ No newline at end of file
+}
+

From e4307c64321db3e7cf4568b571ed6113ca6e297b Mon Sep 17 00:00:00 2001
From: phlangiee <174984579+phlangiee@users.noreply.github.com>
Date: Tue, 18 Nov 2025 02:35:04 -0800
Subject: [PATCH 03/16] Ignores judge to team pair if they were paired before
 (hopefully)

---
 .../_utils/matching/judgesToTeamsAlgorithm.ts      | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
index 31ecc236..74a8cabf 100644
--- a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
+++ b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
@@ -159,13 +159,14 @@ export default async function matchAllTeams(options?: { alpha?: number }) {
       .map((team) => [team._id ?? '', rounds - team.tracks.length])
   );
 
-  // Get previous pairings
+  // Get previous pairings and push it to the judgeToTeam array (so that it triggers duplicate exists??)
   const previousPairings = await GetJudgeToTeamPairings();
-  if (previousPairings.ok) {
-    const isSecondRound = previousPairings.body.length !== 0 ? true : false;
+  if (previousPairings.body) {
+    //const isSecondRound = previousPairings.body.length !== 0 ? true : false; // theres a red line??
+    judgeToTeam.push(...previousPairings.body);
   } else {
     console.log(previousPairings.error);
-    const isSecondRound = false; 
+    //const isSecondRound = false; 
   }
 
   // Main loop: process each team for each round.
@@ -223,6 +224,11 @@ export default async function matchAllTeams(options?: { alpha?: number }) {
     shuffleArray(modifiedTeams);
   }
 
+  // Remove the previous pairings??
+  if (previousPairings.body) {
+    judgeToTeam.splice(0, previousPairings.body.length);
+  }
+
   console.log('No. of judgeToTeam:', judgeToTeam.length);
 
   const judgeAssignments = judgesQueue.map((judge) => judge.teamsAssigned);

From be0cd95215ede70cfb8914585ad75c1564ade9f3 Mon Sep 17 00:00:00 2001
From: phlangiee <174984579+phlangiee@users.noreply.github.com>
Date: Mon, 24 Nov 2025 08:53:24 -0800
Subject: [PATCH 04/16] Fixed bugs: current number of rounds did not match
 validation error checking

---
 app/(api)/_actions/logic/checkMatches.ts            | 4 ++--
 app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/app/(api)/_actions/logic/checkMatches.ts b/app/(api)/_actions/logic/checkMatches.ts
index 54fe18f8..6068cc87 100644
--- a/app/(api)/_actions/logic/checkMatches.ts
+++ b/app/(api)/_actions/logic/checkMatches.ts
@@ -4,7 +4,7 @@ export default function checkMatches(
   matches: Submission[],
   teamsLength: number
 ) {
-  if (matches.length < 3 * teamsLength) return false;
+  if (matches.length < 2 * teamsLength) return false;
 
   let valid = true;
   const mp: Map<string, number> = new Map();
@@ -18,7 +18,7 @@ export default function checkMatches(
   }
 
   mp.forEach((count) => {
-    if (count !== 3) valid = false;
+    if (count !== 2) valid = false;
   });
 
   return valid;
diff --git a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
index 74a8cabf..eca8a26f 100644
--- a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
+++ b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
@@ -161,7 +161,7 @@ export default async function matchAllTeams(options?: { alpha?: number }) {
 
   // Get previous pairings and push it to the judgeToTeam array (so that it triggers duplicate exists??)
   const previousPairings = await GetJudgeToTeamPairings();
-  if (previousPairings.body) {
+  if (previousPairings.ok && previousPairings.body) {
     //const isSecondRound = previousPairings.body.length !== 0 ? true : false; // theres a red line??
     judgeToTeam.push(...previousPairings.body);
   } else {

From 713ea5ec6e3eab0dea9d2b8f4810608d633d285e Mon Sep 17 00:00:00 2001
From: phlangiee <174984579+phlangiee@users.noreply.github.com>
Date: Mon, 24 Nov 2025 09:36:34 -0800
Subject: [PATCH 05/16] Commented out submissions validation error check
 (because current algorithm checks for that)

---
 app/(api)/_actions/logic/matchTeams.ts | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/app/(api)/_actions/logic/matchTeams.ts b/app/(api)/_actions/logic/matchTeams.ts
index 157245ce..4c5bf3ba 100644
--- a/app/(api)/_actions/logic/matchTeams.ts
+++ b/app/(api)/_actions/logic/matchTeams.ts
@@ -11,7 +11,7 @@ import checkMatches from '@actions/logic/checkMatches';
 export default async function matchTeams(
   options: { alpha: number } = { alpha: 4 }
 ) {
-  const submissionsResponse = await GetManySubmissions();
+  /*const submissionsResponse = await GetManySubmissions();
   if (
     submissionsResponse.ok &&
     submissionsResponse.body &&
@@ -23,7 +23,7 @@ export default async function matchTeams(
       error:
         'Submissions collection is not empty. Please clear submissions before matching teams.',
     };
-  }
+  }*/
 
   // Generate submissions based on judge-team assignments.
   const teamsRes = await GetManyTeams();
@@ -46,10 +46,11 @@ export default async function matchTeams(
     }
     const res = await CreateManySubmissions(parsedJudgeToTeam);
     if (!res.ok) {
+      console.log(`${res.error}`);
       return {
         ok: false,
         body: null,
-        error: 'Invalid submissions.',
+        error: 'Invalid submissions.1',
       };
     }
     // for (const submission of parsedJudgeToTeam) {
@@ -65,7 +66,7 @@ export default async function matchTeams(
     return {
       ok: false,
       body: null,
-      error: 'Invalid submissions.',
+      error: 'Invalid submissions.2',
     };
   }
   return {

From b961928c3d285e232a2daa4ae6cafbf4e945f265 Mon Sep 17 00:00:00 2001
From: phlangiee <174984579+phlangiee@users.noreply.github.com>
Date: Mon, 24 Nov 2025 09:38:24 -0800
Subject: [PATCH 06/16] Fixed bug: type mismatch with JudgeToTeam previous
 pairings and the current matches

---
 app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts | 4 ++--
 app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts      | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts b/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
index cf8288a1..88354db3 100644
--- a/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
+++ b/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
@@ -14,8 +14,8 @@ export const GetJudgeToTeamPairings = async () => {
             .toArray();
         
         const pairings = submissions.map((submission: Submission) => ({ 
-            judge_id: submission.judge_id, 
-            team_id: submission.team_id
+            judge_id: String(submission.judge_id), 
+            team_id: String(submission.team_id)
         }));
         // erm im not sure if i did this right??
 
diff --git a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
index eca8a26f..c1fdcabe 100644
--- a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
+++ b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
@@ -182,8 +182,8 @@ export default async function matchAllTeams(options?: { alpha?: number }) {
       for (const judge of judgesQueue) {
         const duplicateExists = judgeToTeam.some(
           (entry) =>
-            entry.judge_id === judge.user._id?.toString() &&
-            entry.team_id === team._id?.toString()
+            String(entry.judge_id) === judge.user._id?.toString() &&
+            String(entry.team_id) === team._id?.toString()
         );
         if (!duplicateExists) {
           selectedJudge = judge;

From 0d1e82b4104749e034a7f90043a5df7f12af64c8 Mon Sep 17 00:00:00 2001
From: phlangiee <174984579+phlangiee@users.noreply.github.com>
Date: Mon, 24 Nov 2025 14:42:37 -0800
Subject: [PATCH 07/16] Fixed comments

---
 app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts | 3 +--
 app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts      | 6 ++----
 2 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts b/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
index 88354db3..fbfc7500 100644
--- a/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
+++ b/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
@@ -17,9 +17,8 @@ export const GetJudgeToTeamPairings = async () => {
             judge_id: String(submission.judge_id), 
             team_id: String(submission.team_id)
         }));
-        // erm im not sure if i did this right??
 
-        return { ok: true, body: pairings as JudgeToTeam[], error: null}; // um not sure if the format in the db is the exact same as the judgetoteam??
+        return { ok: true, body: pairings as JudgeToTeam[], error: null}; 
     } catch (e) {
         const error = e as HttpError;
         return { ok: false, body: null, error: error.message };
diff --git a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
index c1fdcabe..a10ffea9 100644
--- a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
+++ b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
@@ -159,14 +159,12 @@ export default async function matchAllTeams(options?: { alpha?: number }) {
       .map((team) => [team._id ?? '', rounds - team.tracks.length])
   );
 
-  // Get previous pairings and push it to the judgeToTeam array (so that it triggers duplicate exists??)
+  // Get previous pairings and push it to the judgeToTeam array (so that !duplicateExists is true)
   const previousPairings = await GetJudgeToTeamPairings();
   if (previousPairings.ok && previousPairings.body) {
-    //const isSecondRound = previousPairings.body.length !== 0 ? true : false; // theres a red line??
     judgeToTeam.push(...previousPairings.body);
   } else {
     console.log(previousPairings.error);
-    //const isSecondRound = false; 
   }
 
   // Main loop: process each team for each round.
@@ -224,7 +222,7 @@ export default async function matchAllTeams(options?: { alpha?: number }) {
     shuffleArray(modifiedTeams);
   }
 
-  // Remove the previous pairings??
+  // Remove the previous pairings
   if (previousPairings.body) {
     judgeToTeam.splice(0, previousPairings.body.length);
   }

From d96eda6af7937cade10689266f65204e5a650913 Mon Sep 17 00:00:00 2001
From: phlangiee <174984579+phlangiee@users.noreply.github.com>
Date: Mon, 24 Nov 2025 15:52:25 -0800
Subject: [PATCH 08/16] Formatting code (for eslint </3)

---
 app/(api)/_actions/logic/matchTeams.ts        |  2 +-
 .../judgeToTeam/getJudgeToTeamPairings.ts     | 34 +++++++------------
 2 files changed, 14 insertions(+), 22 deletions(-)

diff --git a/app/(api)/_actions/logic/matchTeams.ts b/app/(api)/_actions/logic/matchTeams.ts
index 4c5bf3ba..290d4212 100644
--- a/app/(api)/_actions/logic/matchTeams.ts
+++ b/app/(api)/_actions/logic/matchTeams.ts
@@ -5,7 +5,7 @@ import matchAllTeams from '@utils/matching/judgesToTeamsAlgorithm';
 import parseAndReplace from '@utils/request/parseAndReplace';
 import { GetManyTeams } from '@datalib/teams/getTeam';
 import { CreateManySubmissions } from '@datalib/submissions/createSubmission';
-import { GetManySubmissions } from '@datalib/submissions/getSubmissions';
+//import { GetManySubmissions } from '@datalib/submissions/getSubmissions';
 import checkMatches from '@actions/logic/checkMatches';
 
 export default async function matchTeams(
diff --git a/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts b/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
index fbfc7500..e000ac65 100644
--- a/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
+++ b/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
@@ -1,27 +1,19 @@
 import JudgeToTeam from '@typeDefs/judgeToTeam';
 import { getDatabase } from '@utils/mongodb/mongoClient.mjs';
-import parseAndReplace from '@utils/request/parseAndReplace';
 import { HttpError } from '@utils/response/Errors';
-import { ObjectId } from 'mongodb';
 import Submission from '@typeDefs/submission';
 
 export const GetJudgeToTeamPairings = async () => {
-    try {
-        const db = await getDatabase();
-        const submissions = await db
-            .collection('submissions') 
-            .find()
-            .toArray();
-        
-        const pairings = submissions.map((submission: Submission) => ({ 
-            judge_id: String(submission.judge_id), 
-            team_id: String(submission.team_id)
-        }));
-
-        return { ok: true, body: pairings as JudgeToTeam[], error: null}; 
-    } catch (e) {
-        const error = e as HttpError;
-        return { ok: false, body: null, error: error.message };
-    }
-}
-
+  try {
+    const db = await getDatabase();
+    const submissions = await db.collection('submissions').find().toArray();
+    const pairings = submissions.map((submission: Submission) => ({
+      judge_id: String(submission.judge_id),
+      team_id: String(submission.team_id),
+    }));
+    return { ok: true, body: pairings as JudgeToTeam[], error: null };
+  } catch (e) {
+    const error = e as HttpError;
+    return { ok: false, body: null, error: error.message };
+  }
+};

From d13b25dcf748c40e10c719334e8d9555d6197440 Mon Sep 17 00:00:00 2001
From: Sandeep Reehal <126985041+ReehalS@users.noreply.github.com>
Date: Thu, 29 Jan 2026 16:53:31 -0800
Subject: [PATCH 09/16] Update
 app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
---
 .../_datalib/judgeToTeam/getJudgeToTeamPairings.ts  | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts b/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
index e000ac65..989b43b7 100644
--- a/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
+++ b/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
@@ -2,12 +2,21 @@ import JudgeToTeam from '@typeDefs/judgeToTeam';
 import { getDatabase } from '@utils/mongodb/mongoClient.mjs';
 import { HttpError } from '@utils/response/Errors';
 import Submission from '@typeDefs/submission';
+import { ObjectId } from 'mongodb';
+
+type MongoSubmission = Omit<Submission, 'judge_id' | 'team_id'> & {
+  judge_id: ObjectId;
+  team_id: ObjectId;
+};
 
 export const GetJudgeToTeamPairings = async () => {
   try {
     const db = await getDatabase();
-    const submissions = await db.collection('submissions').find().toArray();
-    const pairings = submissions.map((submission: Submission) => ({
+    const submissions = await db
+      .collection<MongoSubmission>('submissions')
+      .find()
+      .toArray();
+    const pairings = submissions.map((submission) => ({
       judge_id: String(submission.judge_id),
       team_id: String(submission.team_id),
     }));

From aa1cf177e51d0dc027bf282ebe569ea1020306fe Mon Sep 17 00:00:00 2001
From: Sandeep Reehal <126985041+ReehalS@users.noreply.github.com>
Date: Thu, 29 Jan 2026 16:53:54 -0800
Subject: [PATCH 10/16] Force fail if getJudgeToTeamPairings fails

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
---
 app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
index a10ffea9..ce7c2e12 100644
--- a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
+++ b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
@@ -161,11 +161,14 @@ export default async function matchAllTeams(options?: { alpha?: number }) {
 
   // Get previous pairings and push it to the judgeToTeam array (so that !duplicateExists is true)
   const previousPairings = await GetJudgeToTeamPairings();
-  if (previousPairings.ok && previousPairings.body) {
-    judgeToTeam.push(...previousPairings.body);
-  } else {
-    console.log(previousPairings.error);
+  if (!previousPairings.ok || !previousPairings.body) {
+    throw new Error(
+      `Failed to load existing judge-to-team pairings: ${
+        previousPairings.error ?? 'Unknown error'
+      }`
+    );
   }
+  judgeToTeam.push(...previousPairings.body);
 
   // Main loop: process each team for each round.
   for (let domainIndex = 0; domainIndex < rounds; domainIndex++) {

From 66522199ab79f00da4ee9e2c358f12a2557c2c07 Mon Sep 17 00:00:00 2001
From: Sandeep Reehal <126985041+ReehalS@users.noreply.github.com>
Date: Thu, 29 Jan 2026 16:54:59 -0800
Subject: [PATCH 11/16] Defensive check for previousPairings.ok before body
 check

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
---
 app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
index ce7c2e12..4b387787 100644
--- a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
+++ b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
@@ -226,7 +226,7 @@ export default async function matchAllTeams(options?: { alpha?: number }) {
   }
 
   // Remove the previous pairings
-  if (previousPairings.body) {
+  if (previousPairings.ok && previousPairings.body) {
     judgeToTeam.splice(0, previousPairings.body.length);
   }
 

From 000482a382fffa72a5905e6dc22287d374b72e9d Mon Sep 17 00:00:00 2001
From: reehals <sunny.reehal@gmail.com>
Date: Thu, 29 Jan 2026 17:55:33 -0800
Subject: [PATCH 12/16] Update getJudgeToTeamPairings.ts

---
 app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts b/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
index 989b43b7..86bb5fc5 100644
--- a/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
+++ b/app/(api)/_datalib/judgeToTeam/getJudgeToTeamPairings.ts
@@ -2,7 +2,7 @@ import JudgeToTeam from '@typeDefs/judgeToTeam';
 import { getDatabase } from '@utils/mongodb/mongoClient.mjs';
 import { HttpError } from '@utils/response/Errors';
 import Submission from '@typeDefs/submission';
-import { ObjectId } from 'mongodb';
+import { ObjectId, Db } from 'mongodb';
 
 type MongoSubmission = Omit<Submission, 'judge_id' | 'team_id'> & {
   judge_id: ObjectId;
@@ -11,7 +11,7 @@ type MongoSubmission = Omit<Submission, 'judge_id' | 'team_id'> & {
 
 export const GetJudgeToTeamPairings = async () => {
   try {
-    const db = await getDatabase();
+    const db = (await getDatabase()) as Db;
     const submissions = await db
       .collection<MongoSubmission>('submissions')
       .find()

From c79a9a4d2d693fae910ab08136f1a3bd17fad954 Mon Sep 17 00:00:00 2001
From: reehals <sunny.reehal@gmail.com>
Date: Thu, 29 Jan 2026 18:50:50 -0800
Subject: [PATCH 13/16] Update page to allow multiple rounds now.

---
 .../_actions/logic/applyDiagnosticAlpha.ts    | 35 ++++++++++++++-----
 .../JudgeTeamGrouping/JudgeTeamGrouping.tsx   | 13 ++++---
 2 files changed, 34 insertions(+), 14 deletions(-)

diff --git a/app/(api)/_actions/logic/applyDiagnosticAlpha.ts b/app/(api)/_actions/logic/applyDiagnosticAlpha.ts
index cb26d70b..e52815e3 100644
--- a/app/(api)/_actions/logic/applyDiagnosticAlpha.ts
+++ b/app/(api)/_actions/logic/applyDiagnosticAlpha.ts
@@ -14,25 +14,35 @@ import checkMatches from '@actions/logic/checkMatches';
 export default async function applyDiagnosticAlpha(options: {
   alpha: number;
   judgeToTeam: JudgeToTeam[];
-}): Promise<{ ok: boolean; body: JudgeToTeam[] | null; error: string | null }> {
+}): Promise<{
+  ok: boolean;
+  body: JudgeToTeam[] | null;
+  error: string | null;
+  message?: string;
+}> {
   const existing = await GetManySubmissions();
-  if (existing.ok && existing.body && existing.body.length > 0) {
+  const teamsRes = await GetManyTeams();
+  if (!teamsRes.ok) {
     return {
       ok: false,
       body: null,
-      error:
-        'Submissions collection is not empty. Please clear before applying diagnostics.',
+      error: `GetManyTeams error: ${teamsRes.error}`,
     };
   }
-  const teamsRes = await GetManyTeams();
-  if (!teamsRes.ok) {
+  const teams = teamsRes.body;
+  const existingCount = existing.ok && existing.body ? existing.body.length : 0;
+  const maxRounds = 4;
+  const maxSubmissions = teams.length * maxRounds;
+  const isSecondRound = existingCount > 0;
+
+  if (existingCount >= maxSubmissions) {
     return {
       ok: false,
       body: null,
-      error: `GetManyTeams error: ${teamsRes.error}`,
+      error:
+        'Two rounds have already been completed. Clear submissions to rerun.',
     };
   }
-  const teams = teamsRes.body;
   const parsedSubmissions = await parseAndReplace(options.judgeToTeam);
   if (!checkMatches(parsedSubmissions, teams.length)) {
     return {
@@ -62,5 +72,12 @@ export default async function applyDiagnosticAlpha(options: {
   //     return { ok: false, body: null, error: res.error };
   //   }
 
-  return { ok: true, body: options.judgeToTeam, error: null };
+  return {
+    ok: true,
+    body: options.judgeToTeam,
+    error: null,
+    message: isSecondRound
+      ? 'Second round detected: new pairings were added on top of existing submissions.'
+      : undefined,
+  };
 }
diff --git a/app/(pages)/admin/_components/JudgeTeamGrouping/JudgeTeamGrouping.tsx b/app/(pages)/admin/_components/JudgeTeamGrouping/JudgeTeamGrouping.tsx
index aabb46a0..18c021ab 100644
--- a/app/(pages)/admin/_components/JudgeTeamGrouping/JudgeTeamGrouping.tsx
+++ b/app/(pages)/admin/_components/JudgeTeamGrouping/JudgeTeamGrouping.tsx
@@ -130,6 +130,9 @@ export default function JudgeTeamGrouping() {
       setShowSubmissions(true);
       setApplyAlphaSuccess(true);
       setError('');
+      if (res.message) {
+        alert(res.message);
+      }
     } else {
       setError(res.error!);
       setShowMatching(false);
@@ -326,14 +329,14 @@ export default function JudgeTeamGrouping() {
 
   return (
     <div className={styles.body}>
-      <div className="flex items-center gap-4">
-        <h4 style={{ cursor: 'pointer' }}>Error</h4>
-        {error && (
+      {error && (
+        <div className="flex items-center gap-4">
+          <h4 style={{ cursor: 'pointer' }}>Error</h4>
           <div>
             <pre style={{ color: 'red' }}>{error}</pre>
           </div>
-        )}
-      </div>
+        </div>
+      )}
 
       {/* Diagnostics inputs */}
       <div className="mt-6">

From 98e31fcbc50a5724dc57881c9765cb40ad746081 Mon Sep 17 00:00:00 2001
From: reehals <sunny.reehal@gmail.com>
Date: Thu, 5 Feb 2026 20:33:11 -0800
Subject: [PATCH 14/16] Add tests for judgeToTeam

---
 __tests__/datalib/judgeToTeam.ts | 77 ++++++++++++++++++++++++++++++++
 1 file changed, 77 insertions(+)
 create mode 100644 __tests__/datalib/judgeToTeam.ts

diff --git a/__tests__/datalib/judgeToTeam.ts b/__tests__/datalib/judgeToTeam.ts
new file mode 100644
index 00000000..f8e26999
--- /dev/null
+++ b/__tests__/datalib/judgeToTeam.ts
@@ -0,0 +1,77 @@
+import { GetJudgeToTeamPairings } from '@datalib/judgeToTeam/getJudgeToTeamPairings';
+import { setupDatabase, teardownDatabase } from './setup';
+
+describe('Judge To Team Pairings', () => {
+  beforeAll(async () => {
+    await setupDatabase();
+  });
+
+  afterAll(async () => {
+    await teardownDatabase();
+  });
+
+  it('should return empty array when no submissions exist', async () => {
+    const res = await GetJudgeToTeamPairings();
+
+    expect(res.ok).toBe(true);
+    expect(res.body).toEqual([]);
+    expect(res.error).toBeNull();
+  });
+
+  it('should return all judge-to-team pairings with correct structure', async () => {
+    const db = await (await import('@utils/mongodb/mongoClient.mjs')).getDatabase();
+
+    // Insert test submissions
+    const testSubmissions = [
+      {
+        judge_id: db.collection('judges').findOne({}).then((j: any) => j?._id),
+        team_id: db.collection('teams').findOne({}).then((t: any) => t?._id),
+        average_score: 85,
+        round: 1,
+      },
+    ];
+
+    // For now, just test that the function returns in the correct format
+    const res = await GetJudgeToTeamPairings();
+
+    expect(res.ok).toBe(true);
+    expect(Array.isArray(res.body)).toBe(true);
+
+    if (res.body && res.body.length > 0) {
+      // Verify structure of returned pairings
+      const pairing = res.body[0];
+      expect(pairing).toHaveProperty('judge_id');
+      expect(pairing).toHaveProperty('team_id');
+      expect(typeof pairing.judge_id).toBe('string');
+      expect(typeof pairing.team_id).toBe('string');
+    }
+  });
+
+  it('should convert ObjectIds to strings in returned pairings', async () => {
+    const res = await GetJudgeToTeamPairings();
+
+    expect(res.ok).toBe(true);
+
+    if (res.body && res.body.length > 0) {
+      // Verify that all IDs are strings, not ObjectIds
+      for (const pairing of res.body) {
+        expect(typeof pairing.judge_id).toBe('string');
+        expect(typeof pairing.team_id).toBe('string');
+        // ObjectIds have 24 character hex strings or similar patterns
+        // Strings should be valid
+        expect(pairing.judge_id).toBeTruthy();
+        expect(pairing.team_id).toBeTruthy();
+      }
+    }
+  });
+
+  it('should handle database errors gracefully', async () => {
+    // Note: This test would need a mock or a way to trigger DB errors
+    // For now, we just verify the function handles the happy path
+    const res = await GetJudgeToTeamPairings();
+
+    expect(res).toHaveProperty('ok');
+    expect(res).toHaveProperty('body');
+    expect(res).toHaveProperty('error');
+  });
+});

From 2b9832dc41d8f654ff16c7dc90e3ebbe92664e4d Mon Sep 17 00:00:00 2001
From: reehals <sunny.reehal@gmail.com>
Date: Thu, 5 Feb 2026 20:39:54 -0800
Subject: [PATCH 15/16] Update test for judgeToTeam

Also add a comment so Copilot Code Review doesn't complain again.
---
 __tests__/datalib/judgeToTeam.ts              | 171 +++++++++++-------
 .../_utils/matching/judgesToTeamsAlgorithm.ts |   4 +
 2 files changed, 113 insertions(+), 62 deletions(-)

diff --git a/__tests__/datalib/judgeToTeam.ts b/__tests__/datalib/judgeToTeam.ts
index f8e26999..6a339046 100644
--- a/__tests__/datalib/judgeToTeam.ts
+++ b/__tests__/datalib/judgeToTeam.ts
@@ -1,77 +1,124 @@
+import { db } from '../../jest.setup';
 import { GetJudgeToTeamPairings } from '@datalib/judgeToTeam/getJudgeToTeamPairings';
-import { setupDatabase, teardownDatabase } from './setup';
+import { ObjectId } from 'mongodb';
+import JudgeToTeam from '@typeDefs/judgeToTeam';
 
-describe('Judge To Team Pairings', () => {
-  beforeAll(async () => {
-    await setupDatabase();
-  });
+beforeEach(async () => {
+  await db.collection('submissions').deleteMany({});
+});
 
-  afterAll(async () => {
-    await teardownDatabase();
+// Helper to create valid submission documents
+function createSubmission(judgeId: ObjectId, teamId: ObjectId) {
+  return {
+    judge_id: judgeId,
+    team_id: teamId,
+    social_good: null,
+    creativity: null,
+    presentation: null,
+    scores: [],
+    is_scored: false,
+    queuePosition: null,
+  };
+}
+
+describe('GetJudgeToTeamPairings', () => {
+  it('should return an empty array when no submissions exist', async () => {
+    const result = await GetJudgeToTeamPairings();
+    expect(result.ok).toBe(true);
+    expect(result.body).toEqual([]);
+    expect(result.error).toBe(null);
   });
 
-  it('should return empty array when no submissions exist', async () => {
-    const res = await GetJudgeToTeamPairings();
+  it('should return pairings with string IDs converted from ObjectIds', async () => {
+    const judgeId = new ObjectId();
+    const teamId = new ObjectId();
+
+    await db.collection('submissions').insertOne(createSubmission(judgeId, teamId));
 
-    expect(res.ok).toBe(true);
-    expect(res.body).toEqual([]);
-    expect(res.error).toBeNull();
+    const result = await GetJudgeToTeamPairings();
+    expect(result.ok).toBe(true);
+    expect(result.body).toHaveLength(1);
+    expect(result.error).toBe(null);
+
+    const pairing = result.body?.[0];
+    expect(pairing).toEqual({
+      judge_id: judgeId.toString(),
+      team_id: teamId.toString(),
+    });
   });
 
-  it('should return all judge-to-team pairings with correct structure', async () => {
-    const db = await (await import('@utils/mongodb/mongoClient.mjs')).getDatabase();
-
-    // Insert test submissions
-    const testSubmissions = [
-      {
-        judge_id: db.collection('judges').findOne({}).then((j: any) => j?._id),
-        team_id: db.collection('teams').findOne({}).then((t: any) => t?._id),
-        average_score: 85,
-        round: 1,
-      },
-    ];
-
-    // For now, just test that the function returns in the correct format
-    const res = await GetJudgeToTeamPairings();
-
-    expect(res.ok).toBe(true);
-    expect(Array.isArray(res.body)).toBe(true);
-
-    if (res.body && res.body.length > 0) {
-      // Verify structure of returned pairings
-      const pairing = res.body[0];
-      expect(pairing).toHaveProperty('judge_id');
-      expect(pairing).toHaveProperty('team_id');
-      expect(typeof pairing.judge_id).toBe('string');
-      expect(typeof pairing.team_id).toBe('string');
-    }
+  it('should return multiple pairings correctly', async () => {
+    const judgeId1 = new ObjectId();
+    const judgeId2 = new ObjectId();
+    const teamId1 = new ObjectId();
+    const teamId2 = new ObjectId();
+    const teamId3 = new ObjectId();
+
+    await db.collection('submissions').insertMany([
+      createSubmission(judgeId1, teamId1),
+      createSubmission(judgeId1, teamId2),
+      createSubmission(judgeId2, teamId3),
+    ]);
+
+    const result = await GetJudgeToTeamPairings();
+    expect(result.ok).toBe(true);
+    expect(result.body).toHaveLength(3);
+    expect(result.error).toBe(null);
+
+    const pairings = result.body as JudgeToTeam[];
+    expect(pairings[0]).toEqual({
+      judge_id: judgeId1.toString(),
+      team_id: teamId1.toString(),
+    });
+    expect(pairings[1]).toEqual({
+      judge_id: judgeId1.toString(),
+      team_id: teamId2.toString(),
+    });
+    expect(pairings[2]).toEqual({
+      judge_id: judgeId2.toString(),
+      team_id: teamId3.toString(),
+    });
   });
 
-  it('should convert ObjectIds to strings in returned pairings', async () => {
-    const res = await GetJudgeToTeamPairings();
-
-    expect(res.ok).toBe(true);
-
-    if (res.body && res.body.length > 0) {
-      // Verify that all IDs are strings, not ObjectIds
-      for (const pairing of res.body) {
-        expect(typeof pairing.judge_id).toBe('string');
-        expect(typeof pairing.team_id).toBe('string');
-        // ObjectIds have 24 character hex strings or similar patterns
-        // Strings should be valid
-        expect(pairing.judge_id).toBeTruthy();
-        expect(pairing.team_id).toBeTruthy();
-      }
-    }
+  it('should handle duplicate judge-team pairings', async () => {
+    const judgeId = new ObjectId();
+    const teamId = new ObjectId();
+
+    await db.collection('submissions').insertMany([
+      createSubmission(judgeId, teamId),
+      createSubmission(judgeId, teamId),
+    ]);
+
+    const result = await GetJudgeToTeamPairings();
+    expect(result.ok).toBe(true);
+    expect(result.body).toHaveLength(2);
+
+    const pairings = result.body as JudgeToTeam[];
+    expect(pairings[0]).toEqual(pairings[1]);
   });
 
-  it('should handle database errors gracefully', async () => {
-    // Note: This test would need a mock or a way to trigger DB errors
-    // For now, we just verify the function handles the happy path
-    const res = await GetJudgeToTeamPairings();
+  it('should convert ObjectIds to strings for duplicate prevention comparison', async () => {
+    const judgeId = new ObjectId();
+    const teamId = new ObjectId();
+    const judgeIdString = judgeId.toString();
+    const teamIdString = teamId.toString();
+
+    await db.collection('submissions').insertOne(createSubmission(judgeId, teamId));
+
+    const result = await GetJudgeToTeamPairings();
+    const pairings = result.body as JudgeToTeam[];
+
+    // This test verifies that String() conversion is necessary for comparison
+    // in algorithms like judgesToTeamsAlgorithm.ts
+    expect(String(pairings[0].judge_id)).toBe(judgeIdString);
+    expect(String(pairings[0].team_id)).toBe(teamIdString);
 
-    expect(res).toHaveProperty('ok');
-    expect(res).toHaveProperty('body');
-    expect(res).toHaveProperty('error');
+    // Simulate the duplicate check from judgesToTeamsAlgorithm.ts (lines 183-189)
+    const duplicateExists = pairings.some(
+      (entry) =>
+        String(entry.judge_id) === judgeIdString &&
+        String(entry.team_id) === teamIdString
+    );
+    expect(duplicateExists).toBe(true);
   });
 });
diff --git a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
index 4b387787..64409175 100644
--- a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
+++ b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
@@ -181,6 +181,10 @@ export default async function matchAllTeams(options?: { alpha?: number }) {
 
       let selectedJudge: Judge | undefined = undefined;
       for (const judge of judgesQueue) {
+        // String() conversion is necessary because:
+        // - previousPairings from GetJudgeToTeamPairings converts ObjectIds to strings
+        // - judge.user._id and team._id are ObjectIds that need .toString()
+        // - Comparing without String() would cause false negatives in duplicate detection
         const duplicateExists = judgeToTeam.some(
           (entry) =>
             String(entry.judge_id) === judge.user._id?.toString() &&

From 8e0fb4950626f4548bc5b83ec9c24bae52b69412 Mon Sep 17 00:00:00 2001
From: reehals <sunny.reehal@gmail.com>
Date: Thu, 5 Feb 2026 21:01:12 -0800
Subject: [PATCH 16/16] Address copilot comments

---
 __tests__/datalib/judgeToTeam.ts              | 30 ++++++++++++-------
 .../_actions/logic/applyDiagnosticAlpha.ts    |  6 ++--
 app/(api)/_actions/logic/matchTeams.ts        |  6 ++--
 .../_utils/matching/judgesToTeamsAlgorithm.ts | 23 +++++++++++---
 4 files changed, 45 insertions(+), 20 deletions(-)

diff --git a/__tests__/datalib/judgeToTeam.ts b/__tests__/datalib/judgeToTeam.ts
index 6a339046..fb685794 100644
--- a/__tests__/datalib/judgeToTeam.ts
+++ b/__tests__/datalib/judgeToTeam.ts
@@ -33,7 +33,9 @@ describe('GetJudgeToTeamPairings', () => {
     const judgeId = new ObjectId();
     const teamId = new ObjectId();
 
-    await db.collection('submissions').insertOne(createSubmission(judgeId, teamId));
+    await db
+      .collection('submissions')
+      .insertOne(createSubmission(judgeId, teamId));
 
     const result = await GetJudgeToTeamPairings();
     expect(result.ok).toBe(true);
@@ -54,11 +56,13 @@ describe('GetJudgeToTeamPairings', () => {
     const teamId2 = new ObjectId();
     const teamId3 = new ObjectId();
 
-    await db.collection('submissions').insertMany([
-      createSubmission(judgeId1, teamId1),
-      createSubmission(judgeId1, teamId2),
-      createSubmission(judgeId2, teamId3),
-    ]);
+    await db
+      .collection('submissions')
+      .insertMany([
+        createSubmission(judgeId1, teamId1),
+        createSubmission(judgeId1, teamId2),
+        createSubmission(judgeId2, teamId3),
+      ]);
 
     const result = await GetJudgeToTeamPairings();
     expect(result.ok).toBe(true);
@@ -84,10 +88,12 @@ describe('GetJudgeToTeamPairings', () => {
     const judgeId = new ObjectId();
     const teamId = new ObjectId();
 
-    await db.collection('submissions').insertMany([
-      createSubmission(judgeId, teamId),
-      createSubmission(judgeId, teamId),
-    ]);
+    await db
+      .collection('submissions')
+      .insertMany([
+        createSubmission(judgeId, teamId),
+        createSubmission(judgeId, teamId),
+      ]);
 
     const result = await GetJudgeToTeamPairings();
     expect(result.ok).toBe(true);
@@ -103,7 +109,9 @@ describe('GetJudgeToTeamPairings', () => {
     const judgeIdString = judgeId.toString();
     const teamIdString = teamId.toString();
 
-    await db.collection('submissions').insertOne(createSubmission(judgeId, teamId));
+    await db
+      .collection('submissions')
+      .insertOne(createSubmission(judgeId, teamId));
 
     const result = await GetJudgeToTeamPairings();
     const pairings = result.body as JudgeToTeam[];
diff --git a/app/(api)/_actions/logic/applyDiagnosticAlpha.ts b/app/(api)/_actions/logic/applyDiagnosticAlpha.ts
index e52815e3..b77aa4f8 100644
--- a/app/(api)/_actions/logic/applyDiagnosticAlpha.ts
+++ b/app/(api)/_actions/logic/applyDiagnosticAlpha.ts
@@ -31,8 +31,8 @@ export default async function applyDiagnosticAlpha(options: {
   }
   const teams = teamsRes.body;
   const existingCount = existing.ok && existing.body ? existing.body.length : 0;
-  const maxRounds = 4;
-  const maxSubmissions = teams.length * maxRounds;
+  const maxTotalAssignmentsPerTeam = 4;
+  const maxSubmissions = teams.length * maxTotalAssignmentsPerTeam;
   const isSecondRound = existingCount > 0;
 
   if (existingCount >= maxSubmissions) {
@@ -40,7 +40,7 @@ export default async function applyDiagnosticAlpha(options: {
       ok: false,
       body: null,
       error:
-        'Two rounds have already been completed. Clear submissions to rerun.',
+        'Maximum judge assignments reached (4 judges per team). Clear submissions to rerun.',
     };
   }
   const parsedSubmissions = await parseAndReplace(options.judgeToTeam);
diff --git a/app/(api)/_actions/logic/matchTeams.ts b/app/(api)/_actions/logic/matchTeams.ts
index 290d4212..b58fa5a5 100644
--- a/app/(api)/_actions/logic/matchTeams.ts
+++ b/app/(api)/_actions/logic/matchTeams.ts
@@ -50,7 +50,9 @@ export default async function matchTeams(
       return {
         ok: false,
         body: null,
-        error: 'Invalid submissions.1',
+        error: `Failed to create submissions in database: ${
+          res.error ?? 'Unknown error'
+        }`,
       };
     }
     // for (const submission of parsedJudgeToTeam) {
@@ -66,7 +68,7 @@ export default async function matchTeams(
     return {
       ok: false,
       body: null,
-      error: 'Invalid submissions.2',
+      error: 'Invalid submissions: assignment validation failed.',
     };
   }
   return {
diff --git a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
index 64409175..9d029252 100644
--- a/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
+++ b/app/(api)/_utils/matching/judgesToTeamsAlgorithm.ts
@@ -168,7 +168,8 @@ export default async function matchAllTeams(options?: { alpha?: number }) {
       }`
     );
   }
-  judgeToTeam.push(...previousPairings.body);
+  const previousPairingsBody = previousPairings.body;
+  judgeToTeam.push(...previousPairingsBody);
 
   // Main loop: process each team for each round.
   for (let domainIndex = 0; domainIndex < rounds; domainIndex++) {
@@ -229,9 +230,23 @@ export default async function matchAllTeams(options?: { alpha?: number }) {
     shuffleArray(modifiedTeams);
   }
 
-  // Remove the previous pairings
-  if (previousPairings.ok && previousPairings.body) {
-    judgeToTeam.splice(0, previousPairings.body.length);
+  // Remove the previous pairings without relying on array insertion order.
+  if (previousPairingsBody.length > 0) {
+    const previousPairingKeySet = new Set(
+      previousPairingsBody.map((pairing) => {
+        const judgeId = String(pairing.judge_id);
+        const teamId = String(pairing.team_id);
+        return `${judgeId}::${teamId}`;
+      })
+    );
+    const filteredJudgeToTeam = judgeToTeam.filter((entry) => {
+      const judgeId = String(entry.judge_id);
+      const teamId = String(entry.team_id);
+      const key = `${judgeId}::${teamId}`;
+      return !previousPairingKeySet.has(key);
+    });
+    judgeToTeam.length = 0;
+    judgeToTeam.push(...filteredJudgeToTeam);
   }
 
   console.log('No. of judgeToTeam:', judgeToTeam.length);