Try to use the app on another device to see if the issue persists. If it does, then the culprit is most likely the Bluetooth mechanism in the bike. If it is an EX-1 or EX-3, then the console would need to be replaced. If it is an EX-4s, EX-5, EX-5s, Ex-7s, Echelon Sport, Echelon Sport-s, or EX-15, then the bike would need to be replaced. If it doesn't, then the culprit is most likely the original device. If that original device is the mounted tablet found on the "s" model bikes, then the screen would need to be replaced.