Swipe down to check whether the notification arrived silently. Then check Settings → Notifications → App notifications for the affected app and its categories. Review Do Not Disturb or other active modes if alerts are filtered. A missing sound, a hidden lock-screen alert, and a message that never arrived need different checks.
Choose by the missing behavior
Section linkScroll the table sideways to see every column.
| Symptom | First check |
|---|---|
| Alert is in the shade but silent | Category sound and active modes |
| Only one type of app alert is missing | The relevant notification category |
| Alerts disappear only on the lock screen | Lock-screen display settings |
| Problem returns on a schedule | Automatic mode activation |
01Find out what is actually missing
Section linkSwipe down from the top of the screen and look in the notification shade. An alert may already be there even if it made no sound or did not appear on the lock screen. If your phone offers notification history, check for recently dismissed alerts there; the feature and settings vary by device. For example, a visible silent alert is a different problem from content that appears only after opening the app. Record that distinction before changing settings.
02Check the app and the relevant notification category
Section linkOpen Settings → Notifications → App notifications and select the affected app. Check that its notifications are enabled. If it offers categories, inspect the category for the missing alert rather than assuming the overall switch covers every type. You can also touch and hold an existing notification to reach its settings. Menu names vary by manufacturer and Android version. Use the phone maker’s instructions if the displayed controls differ.
03Separate silent alerts from lock-screen visibility
Section linkA Silent notification can still appear when you swipe down, while making no sound or vibration. Check the relevant category’s Alerting or Silent option where available. Some phones also offer a banner or Pop on screen control. If alerts are missing only while locked, check Notifications on lock screen. Choose what you want visible, including whether sensitive content is hidden, rather than enabling every preview just to test.
04Review active modes and their schedules
Section linkCheck Quick Settings for Do Not Disturb and any active Bedtime, Driving, or custom mode. On phones with a Modes menu, open Settings → Modes, select the mode, and inspect its notification filters and schedule. Other devices place these controls elsewhere. A mode can limit allowed apps or hide filtered notifications. Adjust the affected app’s allowance if appropriate. If the problem returns at the same time each day, check automatic activation rather than repeatedly changing the app’s notification switch.
05Test the same event and check inside the app
Section linkOpen the app’s own notification settings too. Android’s permission and the app’s notification preferences are separate checks. Repeat the original event and note whether the alert appears in the shade, makes a sound, and appears while locked. If the content itself appears only when the app opens, report that delivery pattern to the app’s support team with the phone model, Android version, and checks tried. It is a diagnostic clue, not proof that a particular battery setting is responsible.