This time, when I transferred the app to another company (AppTransfer), the push notification did not fly after that. It doesn't go away even after restarting the app, and it seems that no new tokens have been issued. (I don't know if this is due to Firebase or Apple)
The AuthKey seems to be correct because the device that newly installed the app has received the notification.
Firebase is used for push notifications, and the replacement of the AuthKey of the new company account has been completed. Firebase is returning a "Not Registered" response, probably an APNs response "Unregistered".
So, the question is,
(1) Will all tokens become invalid after transferring the app?
(2) Will tokens that have become Unregistered be revived? Is there anything we can do after replacing the certificate?
(3) If this event is not due to AppTransfer, I would like some other advice that we should investigate.
Thank you for reading this far.
