A phone or tablet problem starting right after an OS update, a new case/accessory or a restored backup should be checked against that change first. For Android notification channels, first open the notification history/channel from a missed alert and send an in-app test.
What this covers
- Android notification channels with this exact failure state
- Diagnosis across app-wide permission versus one disabled channel, Focus and battery restriction
What it does not cover
Try in this order
0 of 4 completedCapture the exact failure state
ReversibleNote the exact update version, accessory or backup date, and confirm the feature worked immediately before it. Expected behavior: deliver each alert category with the selected sound, visibility and priority.
Isolate the component boundary
ReversibleOpen the notification history/channel from a missed alert and send an in-app test. Test with the new accessory removed, or check the update's known-issues note for the exact symptom. Boundary to separate: app-wide permission versus one disabled channel, Focus and battery restriction.
Correct only the proven cause
ReversibleEnable only the needed channel and allow appropriate background activity. Reset the one setting the update changed, or replace the incompatible accessory.
Verify and stop safely
ReversibleConfirm normal operation with the change present for one full day of typical use. Preserve emergency and security alerts; do not disable all battery protection.
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