Gmail Notifications Not Working: How to Fix It

Try these in order

1. Turn Gmail notifications back on inside the app. Open Gmail, tap Menu > Settings > General settings > Manage notifications, and switch All Gmail notifications on (Google Help).
2. Set the notification type for each account. In Gmail, tap Menu > Settings, select your account, tap Email notifications under Notifications, and pick the types you want — choose All if you want an alert for every message. If you have several accounts, do this for each one (Asurion).
3. Check Android's own notification settings. Gmail's in-app settings can't override the system — make sure Gmail notifications haven't been switched off at the device level (Asurion).
4. Turn off Do Not Disturb, or add Gmail as an exception. Gmail can keep receiving mail while Do Not Disturb silently hides every alert, so switch it off or allow Gmail through (Asurion).
5. Disable Power Saver and battery optimisation for Gmail. Both limit background syncing, and when syncing slows down, notifications slow down or stop with it. Turn them off temporarily and see if alerts come back (Asurion).
6. Make sure "Sync Gmail" is ticked. In Menu > Settings > [your account], confirm the Sync Gmail box is checked — Google points straight at this when notifications go missing (Google Help).
7. Check label-level notification settings. By default only your Primary label notifies you. To get alerts for another label, go to Menu > Settings > [account] > Manage labels, pick the label, set Sync messages to Last 30 days or All, then choose its notification settings (Google Help).