A. 1. Check notification settings: Go to 'Settings' > 'Apps' > 'Gmail' > 'Notifications' and ensure notifications are enabled. 2. Disable battery optimization: Go to 'Settings' > 'Battery' > 'Battery Optimization', find Gmail, and select 'Don't optimize'. This allows Gmail to run in the background without restrictions.

B. 3. Sync settings: Open Gmail, tap the menu icon, go to 'Settings', select your account, and ensure 'Sync Gmail' is checked. 4. Clear app cache: As mentioned earlier, clearing the cache can also help with notification delays.