diff --git a/Classes/EventListener/SyncChangesToTranslations.php b/Classes/EventListener/SyncChangesToTranslations.php
index 29045cf..b71b6e5 100644
--- a/Classes/EventListener/SyncChangesToTranslations.php
+++ b/Classes/EventListener/SyncChangesToTranslations.php
@@ -172,8 +172,9 @@ private function updateTranslation(
         $tcaColumns = $GLOBALS['TCA'][$table]['columns'];
         $updateColumns = [];
         foreach ($tcaColumns as $columnName => $columnDefinition) {
-            if ($columnDefinition['config']['type'] !== 'inline' &&
-                $columnDefinition['l10n_mode'] === 'exclude'
+            if ($columnDefinition['config']['type'] !== 'inline'
+                && isset($columnDefinition['l10n_mode'])
+                && $columnDefinition['l10n_mode'] === 'exclude'
             ) {
                 $updateColumns[] = $columnName;
             }