diff --git a/lib/questionlib.php b/lib/questionlib.php
index 859e4247276..470b3bead76 100644
--- a/lib/questionlib.php
+++ b/lib/questionlib.php
@@ -560,7 +560,7 @@ function question_move_question_tags_to_new_context(array $questions, context $n
     $questionstagobjects = core_tag_tag::get_items_tags('core_question', 'question', $questionids);
 
     foreach ($questions as $question) {
-        $tagobjects = $questionstagobjects[$question->id];
+        $tagobjects = $questionstagobjects[$question->id] ?? [];
 
         foreach ($tagobjects as $tagobject) {
             $tagid = $tagobject->taginstanceid;