diff --git a/typo3/sysext/backend/Classes/Form/FormDataProvider/TcaFlexProcess.php b/typo3/sysext/backend/Classes/Form/FormDataProvider/TcaFlexProcess.php
index 343ffb41ee8b1132b1b81958882139ecab0a4df1..55eca13e16b521e8c31cbd40ca3f782c23eb32d1 100644
--- a/typo3/sysext/backend/Classes/Form/FormDataProvider/TcaFlexProcess.php
+++ b/typo3/sysext/backend/Classes/Form/FormDataProvider/TcaFlexProcess.php
@@ -570,7 +570,7 @@ class TcaFlexProcess implements FormDataProviderInterface
         $flexFormContainerIdentifier = $flexSectionContainerPreparation['flexFormContainerIdentifier'];
 
         $containerConfiguration = $result['processedTca']['columns'][$fieldName]['config']['ds']
-            ['sheets'][$flexFormSheetName]['ROOT']['el'][$flexFormFieldName]['el'][$flexFormContainerName];
+            ['sheets'][$flexFormSheetName]['ROOT']['el'][$flexFormFieldName]['el'][$flexFormContainerName] ?? [];
 
         if (isset($containerConfiguration['el']) && is_array($containerConfiguration['el'])) {
             $formDataGroup = GeneralUtility::makeInstance(FlexFormSegment::class);