diff --git a/apps/course/serializers/lesson.py b/apps/course/serializers/lesson.py
index 4a26e99..50fd1df 100644
--- a/apps/course/serializers/lesson.py
+++ b/apps/course/serializers/lesson.py
@@ -58,7 +58,8 @@ class CourseLessonSerializer(serializers.ModelSerializer):
 
     def get_quizs(self, obj):
         # Assuming the related_name for quizzes is now on CourseLesson
-        quizzes = obj.quizzes.all() if hasattr(obj, 'quizzes') else []
+        print(f'--> type:{type(obj)}  obj:{obj.lesson.quizzes.all()}')
+        quizzes = obj.lesson.quizzes.all() if hasattr(obj.lesson, 'quizzes') else []
         if quizzes:
             return QuizListSerializer(quizzes, many=True, context=self.context).data
         return None
\ No newline at end of file
diff --git a/apps/quiz/serializers/quiz.py b/apps/quiz/serializers/quiz.py
index 2a9a133..3fdc8e9 100644
--- a/apps/quiz/serializers/quiz.py
+++ b/apps/quiz/serializers/quiz.py
@@ -23,7 +23,14 @@ class QuizListSerializer(serializers.ModelSerializer):
             return False 
         # Check if the user has participated in this quiz
         user = request.user
-        course = obj.lesson.course 
+        
+        # Get the course through CourseLesson model
+        from apps.course.models.lesson import CourseLesson
+        course_lesson = CourseLesson.objects.filter(lesson=obj.lesson).first()
+        if not course_lesson:
+            return False
+            
+        course = course_lesson.course
            
         if not self._is_participant(user, course):
             return False
@@ -78,5 +85,19 @@ class QuizSerializer(serializers.ModelSerializer):
             return False 
         # Check if the user has participated in this quiz
         user = request.user
+        
+        # Get the course through CourseLesson model
+        from apps.course.models.lesson import CourseLesson
+        course_lesson = CourseLesson.objects.filter(lesson=obj.lesson).first()
+        if not course_lesson:
+            return False
+            
+        course = course_lesson.course
+           
+        # Check if user is a participant in the course
+        from apps.course.models import Participant
+        if not Participant.objects.filter(student=user, course=course).exists():
+            return False
+            
         participated = QuizParticipant.objects.filter(user=user, quiz=obj).exists()
         return not participated