Update app.py

app.py

@@ -38,11 +38,9 @@ qa = ConversationalRetrievalChain.from_llm(
     retriever=retriever
 )
 
-chat_history = []
-
 # --- 5️⃣ Respond function ---
 def respond(message, chat_history):
-    global chat_history
+    chat_history = chat_history or []
     chat_history = chat_history[-6:]  # keep last 3 exchanges
     result = qa({"question": message, "chat_history": chat_history})
     chat_history.append((message, result["answer"]))
@@ -86,7 +84,7 @@ with gr.Blocks() as demo:
 
     def exit_case():
         return (
-            gr.update(value="<h2>Session ended. You exited the simulation.</h2>"),  # hide warning text
+            gr.update(value="<h2>Session ended. You exited the simulation.</h2>"),  # hide warning
             gr.update(visible=False),  # chatbot
             gr.update(visible=False),  # user_input
             gr.update(visible=False),  # submit_btn
@@ -115,3 +113,4 @@ with gr.Blocks() as demo:
 # --- 7️⃣ Launch ---
 if __name__ == "__main__":
     demo.launch(share=True, enable_queue=True)
+