diff --git a/app/controllers/course/basicdata.php b/app/controllers/course/basicdata.php
index cda28d74ec39e3a1d5d8f8dea7288c6f29982ea6..1df3a203343733aae3201ea89bb8b991eb6b0bf5 100644
--- a/app/controllers/course/basicdata.php
+++ b/app/controllers/course/basicdata.php
@@ -703,7 +703,7 @@ class Course_BasicdataController extends AuthenticatedController
         } else {
             $sem = Seminar::getInstance($course_id);
             $deputy = Deputy::find([$deputy_id, $course_id]);
-            if ($deputy && $deputy->delete) {
+            if ($deputy && $deputy->delete()) {
                 // Remove user from subcourses as well.
                 if($sem->children) {
                     $children_ids = $sem->children->pluck('seminar_id');
@@ -903,4 +903,4 @@ class Course_BasicdataController extends AuthenticatedController
         }
         return $sem_types;
     }
-}
\ No newline at end of file
+}