diff --git a/lib/models/Statusgruppen.php b/lib/models/Statusgruppen.php
index 30d2149d8a59ddeabdb520f4d8f3f388e5e0401f..68b902f62acd7cca523449bcbc42670d485d0dea 100644
--- a/lib/models/Statusgruppen.php
+++ b/lib/models/Statusgruppen.php
@@ -143,6 +143,8 @@ class Statusgruppen extends SimpleORMap implements PrivacyObject
         // Set assigned dates.
         if ($dates) {
             $group->dates = CourseDate::findMany($dates);
+        } else {
+            $group->dates = [];
         }
 
         $group->store();