diff --git a/cvat/apps/engine/tests/test_rest_api.py b/cvat/apps/engine/tests/test_rest_api.py
index 00d6d0d48e91..36eac8b6dd73 100644
--- a/cvat/apps/engine/tests/test_rest_api.py
+++ b/cvat/apps/engine/tests/test_rest_api.py
@@ -747,7 +747,7 @@ def test_api_v2_users_id_no_auth(self):
 class UserPartialUpdateAPITestCase(UserAPITestCase):
     def _run_api_v2_users_id(self, user, user_id, data):
         with ForceLogin(user, self.client):
-            response = self.client.patch('/api/users/{}'.format(user_id), data=data)
+            response = self.client.patch('/api/users/{}'.format(user_id), data=data, format='json')
 
         return response