Notifications are declined

Steps to reproduce

I first started with just installing Nextcloud Talk from Google Play. After I logged in, it has shown an endless spinner, which I was able to overcome only by removing the app from recent apps and re-opening it. After that, it requested notification permission (which I of course allowed) and has shown a message asking to disable battery optimization. I did it and started testing the app. First I called from that Android phone to an iOS device which was really smooth. I then tried to do backwards, from iOS to Android and it didn't work. I looked in settings and noticed it says "Notifications are declined". I have tried push check which said that push was sent but failed. I tried to disable and re-enable notifications in system settings. I tried adb shell pm grant com.nextcloud.talk android.permission.POST_NOTIFICATIONS. I tried force stop. I tried to clear the settings and enable notification permission before the first run. Nothing has helped.

I then tried to install the F-Droid version in a hope that it will either maintain a direct connection to the Nextcloud server or allow to use Unified Push. But no, it just said that notifications are unsupported. An interesting thing is that it doesn't show the spinner, it shows the conversation list just after login!

I then tried to enable beta testing in Google Play hoping it will provide 21.1.0 RC1 but no, it didn't happen. So I installed the gplay 22.1.0 RC1 version from GitHub releases hoping it will work. But no, it was absolutely the same with the only difference that login was via the default system browser, but after login I got the spinner again. After removing the app from recents and re-opening it, I've got the notification permission request and the same "Notifications are declined" state.

Expected behaviour

Notifications are granted

Actual behaviour

Notifications are declined

Device brand and model

Sony XQ-DQ72

Android version

15

Nextcloud Talk app version

22.0.3, 22.1.0 RC1

Nextcloud server version

32.0.3

Talk version

22.0.7

Custom Signaling server configured

No

Custom TURN server configured

No

Custom STUN server configured

No

Android logs

Language is set to ru
Private user key size: 1708
Public user key size: 451

Found 2 devices registered for push notifications
Identified 2 Talk devices and 0 others.
Trying to push to 2 devices

Device token: 3
Device token is valid
Device public key size: 450
Data to encrypt is: {"nid":17,"app":"admin_notification_talk","subject":"Testing push notifications","type":"admin_notifications","id":"69551a39"}
Signed encrypted push subject

Device token: 18
Device token is valid
Device public key size: 450
Data to encrypt is: {"nid":17,"app":"admin_notification_talk","subject":"Testing push notifications","type":"admin_notifications","id":"69551a39"}
Signed encrypted push subject

Push notification sent, but 1 failed

Server log

nextcloud.log

Additional information

Signaling server version is 2.0.4~docker. Not sure whether that all counts as custom actually, I installed it all via AIO and signaling, STUN ad TURN servers were auto-configured.

I'm not sure whether that's related but I see a lot of "notifications don't work" reviews on Google Play.

Start by reviewing the Android logs and the push-check behavior described in the issue, comparing the Google Play and F-Droid versions on Android 15. Trace why one registered device fails and why the app reports notifications as declined. Done means push notifications are granted and delivered reliably, with the reported failure reproduced or explained.