WhatsApp for Infinix Zero 40 Ultra

XOS aggressively kills background apps to save battery, which stops WhatsApp calls from ringing or appearing. Go to Settings > Apps > WhatsApp > Battery and set it to Unrestricted (No restrictions), then in Settings > Battery, open Phone Manager / App freezer and remove WhatsApp from the auto-cleanup and freeze lists. Also confirm WhatsApp has the 'Display over other apps' permission (Settings > Apps > WhatsApp > Permissions or Special app access) so the incoming-call screen can show. See how others solved this on Reddit

Delayed notifications are almost always XOS power management putting WhatsApp to sleep in the background. Open Settings > Apps > WhatsApp > Battery and choose Unrestricted, then go to Settings > Battery and turn off any 'Smart power saving' or 'Ultra power saving' mode that throttles background data. Locking WhatsApp in the Recent apps screen (tap the app's icon or the lock icon at the top of its card) also helps keep it alive on XOS. See how others solved this on Reddit

The full-screen incoming-call UI needs the overlay permission plus lock-screen notification visibility, which XOS often restricts. Go to Settings > Apps > WhatsApp > Permissions (or Special app access) and enable 'Display over other apps'. Then in Settings > Notifications & status bar > WhatsApp > Calls, set the channel to Pop-up/Urgent and make sure 'Show on lock screen' notifications are allowed for WhatsApp under Settings > Notifications > Lock screen. See how others solved this on Reddit

This happens when WhatsApp's notification channel loses its sound or Android marks it low-priority. In WhatsApp go to Settings > Notifications and re-pick a Notification tone for messages and groups, then on the phone open Settings > Notifications & status bar > WhatsApp > Messages and set Importance to 'Make sound and pop up'. Also check that Do Not Disturb and any scheduled silent mode in Settings > Sound aren't active. See how others solved this on Reddit

Since the Zero 40 Ultra runs Android, back up on your old phone first via WhatsApp > Settings > Chats > Chat backup to Google Drive, using the same Google account you'll sign into on the new device. On the Infinix, install WhatsApp from the Play Store, verify the same phone number, and when prompted choose Restore from Google Drive. Note that iPhone-to-Android transfers can't use Drive and need WhatsApp's 'Move to Android' tool with a USB-C cable instead. See how others solved this on Reddit

XOS major updates sometimes ship with missing settings or broken notifications that a cache clear usually fixes. Go to Settings > Apps > WhatsApp > Storage and tap Clear cache (not Clear data), then restart the phone and re-check your notification and battery permissions, which updates often reset. If features are still missing, look for a follow-up patch in Settings > System > System update, since Infinix typically pushes a quick hotfix after a big XOS release. See how others solved this on Reddit