diff --git a/openedx/core/djangoapps/user_authn/views/register.py b/openedx/core/djangoapps/user_authn/views/register.py
index 0fc2c941158b..e535abeb40b6 100644
--- a/openedx/core/djangoapps/user_authn/views/register.py
+++ b/openedx/core/djangoapps/user_authn/views/register.py
@@ -758,4 +758,10 @@ def post(self, request):
                 validation_decisions.update({
                     form_field_key: handler(self, request)
                 })
+
+        field_name = request.data.get('fieldName')  # adding field name for authn MFE use case
+        if field_name:
+            validation_decisions.update({
+                'fieldName': field_name
+            })
         return Response({"validation_decisions": validation_decisions})