diff --git a/app/views/courses/attahcment_category_list.json.jbuilder b/app/views/courses/attahcment_category_list.json.jbuilder
index 217b1092e..b9acdfe68 100644
--- a/app/views/courses/attahcment_category_list.json.jbuilder
+++ b/app/views/courses/attahcment_category_list.json.jbuilder
@@ -3,8 +3,11 @@ json.course_modules do
   json.array! @course_modules do |course_module|
     json.id course_module.id
     json.module_name course_module.module_name
-    json.course_second_categories do
-      json.array! course_module.course_second_categories, :id, :name
+    json.course_second_categories course_module.first_categories do |category|
+      json.(category, :id, :name)
+      json.course_third_categories category.children do |child|
+        json.(child, :id, :name)
+      end
     end
   end
 end