iOS returns the FCM token, but the cloud uses firebase-admin and it shows UNREGISTERED. How can I fix this problem?

[songzhiming]

iOS returns the FCM token, but the cloud uses firebase-admin and it shows UNREGISTERED. How can I fix this problem?

[google-oss-bot]

I couldn't figure out how to label this issue, so I've labeled it for a human to triage. Hang tight.

[songzhiming]

this is cloud log

[rizafran]

Hi @songzhiming, with the unregistered error, the existing registration token can be rendered invalid in the following scenarios:

• If the client app unregisters with FCM.
• If the client app is automatically unregistered, which can happen if the user uninstalls the application. For example, on iOS, if the APNS Feedback Service reported the APNS token as invalid
• If the registration token expires (for example, Google might decide to refresh registration tokens, or the APNS token has expired for iOS devices).
• If the client app is updated but the new version is not configured to receive messages.

For these cases, you may remove this registration token from the app server and stop using it to send messages.

If the issue persists, it's possible that this might be a backend issue. In this case, please file a ticket through our support channel so the team could investigate your project.