Dialog submission always timeout

[cisco-cx-lab]

I use flask as web api server and define the function for request url from slack interactive component. Inside the interactive function I call another function to make device config change via ssh. After submit dialog, the dialog wont close and always print 'We had some trouble connecting. Try again?" on top of the dialog. The rest functions will run but dialog can only be closed from 'Cancel' button. Is there a way to avoid this timeout issue? Or continue run other functions after submit the dialog? Here is the code for interactive function. Can you help?

=== @app.route('/user_input', methods=['POST']) #read user entered information def user_input(): global qos_input qos_input=json.loads(request.form["payload"]) verify() config() return make_response("",200)