diff --git a/api/db/services/dialog_service.py b/api/db/services/dialog_service.py
index 32de922ab1..cadf76c2aa 100644
--- a/api/db/services/dialog_service.py
+++ b/api/db/services/dialog_service.py
@@ -594,8 +594,7 @@ async def async_chat(dialog, messages, stream=True, **kwargs):
         )
 
     if prompt_config.get("keyword", False):
-        questions[-1] += await keyword_extraction(chat_mdl, questions[-1])
-
+        questions[-1] = questions[-1] + "," + await keyword_extraction(chat_mdl, questions[-1])
     refine_question_ts = timer()
 
     thought = ""