trying query engine

backend.py

@@ -244,7 +244,7 @@ def handle_query(query_str: str,
         
         #chat_engine.reset()
         outputs = []
-        response = query_engine.query(query_str, chat_history=conversation)
+        response = query_engine.query(query_str) 
         #response = chat_engine.stream_chat(query_str, chat_history=conversation)
 
         sources = []  # Use a list to collect multiple sources if present