WhatsApp for Realme 10

Realme UI's aggressive battery management is the usual culprit, so go to Settings > Apps > App management > WhatsApp > Battery usage and set it to Allow background activity / Don't optimize. Then open Settings > Battery and disable Sleep standby optimization, and long-press the WhatsApp icon, pick App info > Allow auto-launch so it can wake in the background. Finally make sure WhatsApp's own notifications are enabled under WhatsApp > Settings > Notifications. See how others solved this on Reddit

This happens when Realme UI freezes WhatsApp in the background, so lock it in Recent apps by swiping down on the WhatsApp card (or long-pressing it) and tapping the lock icon so it isn't cleared. Then go to Settings > Apps > App management > WhatsApp > Battery usage > Allow background activity, and enable Allow auto-launch from the same App info screen. If it persists after a Realme UI update, clear WhatsApp's cache via App info > Storage usage > Clear cache. See how others solved this on Reddit

Both phones must use the same Google account, so on your old phone open WhatsApp > Settings > Chats > Chat backup and back up to Google Drive first. On the Realme 10, install WhatsApp from the Play Store, verify the same phone number, and when prompted tap Restore from your Google Drive backup. If the restore prompt never appears, confirm the Realme 10 is signed into the matching Google account under Settings > Users & accounts. See how others solved this on Reddit

A restore only works when the backup was made under the exact same Google account and phone number, so verify the same number first, then check the old backup exists at WhatsApp > Settings > Chats > Chat backup. On the Realme 10 ensure Google Play services is up to date and that the device is connected to Wi-Fi, since large backups stall on mobile data. If WhatsApp skips the restore screen, uninstall and reinstall it so the verification flow offers the Google Drive backup again. See how others solved this on Reddit

This is usually the proximity sensor misreading and blanking the screen, so first wipe the area near the earpiece and remove any thick screen protector covering the sensor. Then go to Settings > Apps > App management > WhatsApp > Battery usage and allow background activity so the call isn't throttled, and turn off any aggressive power saver during calls. If it continues, update both Realme UI (Settings > About device > software update) and WhatsApp, since a stale build often causes the blackout. See how others solved this on Reddit

This is a Realme UI theming glitch where the gesture/navigation bar doesn't follow the app's dark mode. Force the whole system dark by going to Settings > Display & brightness > Dark mode and turning it on system-wide, which keeps the navigation bar dark inside WhatsApp. Switching to full-screen gesture navigation under Settings > Convenience aids > System navigation also removes the mismatched button bar entirely. See how others solved this on Reddit