diff --git a/public/main/inc/lib/course.lib.php b/public/main/inc/lib/course.lib.php
index 9ad143e9ab..47ce26f39d 100644
--- a/public/main/inc/lib/course.lib.php
+++ b/public/main/inc/lib/course.lib.php
@@ -458,6 +458,7 @@ class CourseManager
                 }
             }
 
+            $user_id = api_get_user_id();
             Event::addEvent(
                 LOG_UNSUBSCRIBE_USER_FROM_COURSE,
                 LOG_COURSE_CODE,