diff --git a/lib/view/pages/timetable/timetable.dart b/lib/view/pages/timetable/timetable.dart
index 5f3385d..715ede1 100644
--- a/lib/view/pages/timetable/timetable.dart
+++ b/lib/view/pages/timetable/timetable.dart
@@ -302,7 +302,7 @@ class _TimetableState extends State<Timetable> {
         var startTime = _parseWebuntisTimestamp(element.date, element.startTime);
         var endTime = _parseWebuntisTimestamp(element.date, element.endTime);
 
-        var subject = subjects.result.firstWhereOrNull((subject) => subject.id == element.su.first.id);
+        var subject = subjects.result.firstWhereOrNull((subject) => subject.id == element.su.firstOrNull?.id);
         var subjectName = 'Unbekannt';
         if(subject != null) {
           subjectName = {