A phone or tablet feature that has completely stopped should be checked for a disabled permission or setting before assuming hardware failure. 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
ReversibleCheck whether the feature is grayed out, missing from settings entirely, or present but unresponsive when used. 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 the same feature in a different app that uses it, and with recently installed apps disabled or in Safe Mode. 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. Re-enable the permission or setting, or update/reinstall the one app where it fails.
Verify and stop safely
ReversibleConfirm the feature works from a cold restart in at least two different apps. Preserve emergency and security alerts; do not disable all battery protection.
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