Update app.py

app.py

@@ -388,7 +388,7 @@ with gr.Blocks(css="constants/styles.css", theme=gr.themes.Soft()) as demo:
         chat_stream, 
         [cur_arxiv_id, local_data, prompt_txtbox, chat_state],
         [prompt_txtbox, chatbot, local_data, close, reset, regen],
-        concurrency_limit=20,
+        concurrency_limit=20, queue=True
     ).then(
         None, [cur_arxiv_id, local_data], None, 
         js=UPDATE_CHAT_HISTORY