Open Can't use Join on my android devices anymore

Hey,
since a few days/since I reinstalled my phone and tablet I cant register my devices to my Join account anymore.

Since I restored the App and Data I always get the error on both devices
"GCM ID no longer registered or invalid", normally I go to my Picture, deregister and reregister the device, that always worked in the past, but not this time.

I already tried to clear cache and data, completely uninstalled and reinstalled from the play store(without TitanBackup), changed the Device names on Join and in the system, even changed my Android Device IDs, but I can not register both, even with just one device added I will get this error after some times.

What's the problem and how can I fix it?

 

Yes that could be, but I already cleared cache and data and uninstalled and reinstalled just from play store, without restoring the backup. But I can't get it to work anymore.

 

Yeah but how can I fix it now?

I already tried wiping app data and reinstalling it from the play store without restoring the backup but the problem don't go.