@Ad_assal How do you close the process? You need to exit it using terminal and then open ngrok again for it to work properly. Or the other case would be that (it happens with many people) after closing ngrok and instantly you again open it would not work as the services running before were not closed so if you open ngrok again it will give you error due to service still closing in background. What you can do is that after shutting down ngrok wait for few minutes and then try again. Or if the problem contninues use different port.