I would start with force closing the app should help. 

On Android if you go to the settings and search for apps, find the Surfboard Central app then tap on Force Stop. 

On iPhone I think you just swipe up to the middle of the screen and then swipe up on the app that is opened in the background. 

If this doesn’t work, you can try and uninstall and reinstall the app. After you reinstall the app, you should just need the same username that you initially used to set it up and get logged back in.