diff --git a/Classes/Step/TransformDataStep.php b/Classes/Step/TransformDataStep.php
index e646b39..cc09cb2 100644
--- a/Classes/Step/TransformDataStep.php
+++ b/Classes/Step/TransformDataStep.php
@@ -23,6 +23,7 @@
 use Cobweb\ExternalImport\ImporterAwareInterface;
 use Cobweb\ExternalImport\Utility\MappingUtility;
 use Symfony\Component\ExpressionLanguage\ExpressionLanguage;
+use TYPO3\CMS\Core\Messaging\AbstractMessage;
 use TYPO3\CMS\Core\Utility\GeneralUtility;
 use TYPO3\CMS\Extbase\Utility\LocalizationUtility;
 
@@ -252,6 +253,11 @@ public function applyUserFunction(string $name, array $configuration, array $rec
                 } catch (InvalidRecordException $e) {
                     // This exception means that the record must be removed from the dataset entirely
                     unset($records[$index]);
+
+                    $this->importer->addMessage(
+                        $e->getMessage(),
+                        AbstractMessage::WARNING
+                    );
                     $this->importer->debug(
                         LocalizationUtility::translate(
                             'LLL:EXT:external_import/Resources/Private/Language/ExternalImport.xlf:invalidRecordRemoved',
@@ -270,6 +276,11 @@ public function applyUserFunction(string $name, array $configuration, array $rec
                 } catch (\Exception $e) {
                     // If the value could not be transformed, remove it from the imported dataset
                     unset($records[$index][$name]);
+
+                    $this->importer->addMessage(
+                        $e->getMessage(),
+                        AbstractMessage::WARNING
+                    );
                     $this->importer->debug(
                         LocalizationUtility::translate(
                             'LLL:EXT:external_import/Resources/Private/Language/ExternalImport.xlf:transformationFailedWithMessage',