Can I automatically unregister device

If I register multiple device with the same user ID, the system will add new device to that user. Is there a way to automatically expire or unregister old device in case the user has permanently changed their phone?

We don’t offer automatic expiry right now - however givent that device IDs changed for every phone and app installation, this shouldn’t cause any problem on the user experience side. If a customer change his/her phone and old phone is resold to the new user, the new user will get a new device ID - so tehre should never been any clashing in devices