Update app.py

app.py

@@ -99,7 +99,7 @@ for message in st.session_state.messages:
     with st.chat_message(message["role"]):
         col1, col2 = st.columns([9,1])
         col1.markdown(message["content"])
-        col2.button("remove", key="button_remove_message", args=[pos], on_click=remove_message)
+        col2.button("remove", key="button_remove_message_"+str(pos), args=[pos], on_click=remove_message)
 
 
 if "remove" not in st.session_state: