diff --git a/Modules/Survey/classes/class.ilObjSurvey.php b/Modules/Survey/classes/class.ilObjSurvey.php
index 69b33a5b046c..c575cafc9f26 100755
--- a/Modules/Survey/classes/class.ilObjSurvey.php
+++ b/Modules/Survey/classes/class.ilObjSurvey.php
@@ -2905,7 +2905,7 @@ public function getQuestionblocksTable(
                     $questions_array[$key] = "$counter. $value";
                     $counter++;
                 }
-                if (strlen($surveytitles[$row["obj_fi"]])) { // only questionpools which are not in trash
+                if (strlen($surveytitles[$row["obj_fi"]] ?? "")) { // only questionpools which are not in trash
                     $rows[$row["questionblock_id"]] = array(
                         "questionblock_id" => $row["questionblock_id"],
                         "title" => $row["title"],