diff --git a/lms/djangoapps/shoppingcart/admin.py b/lms/djangoapps/shoppingcart/admin.py
index c2d5362551..e0f766a327 100644
--- a/lms/djangoapps/shoppingcart/admin.py
+++ b/lms/djangoapps/shoppingcart/admin.py
@@ -72,7 +72,7 @@ class CourseRegistrationCodeInvoiceItemInline(admin.StackedInline):
         'course_id',
     )
 
-    def has_add_permission(self, request):
+    def has_add_permission(self, request, obj=None):
         return False