diff --git a/osm_nbi/base_topic.py b/osm_nbi/base_topic.py
index 9572409..c67ec76 100644
--- a/osm_nbi/base_topic.py
+++ b/osm_nbi/base_topic.py
@@ -147,7 +147,7 @@
             if count >= quota:
                 name = proj["name"]
                 raise ValidationError("quota ({}={}) exceeded for project {} ({})".format(quota_name, quota, name, pid),
-                                      http_code=HTTPStatus.UNAUTHORIZED)
+                                      http_code=HTTPStatus.UNPROCESSABLE_ENTITY)
 
     def _validate_input_new(self, input, force=False):
         """