That's kind of a vague generic error code. I can't recall it being mentioned in connection with TiviMate. I may indicate a poor internet connection simply requiring a restart of the app and gateway. I would first start by clearing the cache, force stopping the app, and restarting. If that doesn't help, try shutting down your gateway for a few minutes and try again. If that fails, you might want to reinstall the app. Create a backup before uninstalling.