WhatsApp for Xiaomi Mi Mix

MIUI's aggressive battery management freezes WhatsApp in the background, so messages only arrive when you open the app. Go to Settings > Apps > Manage apps > WhatsApp, tap 'Battery saver' and set it to 'No restrictions', then on the same WhatsApp app page turn on 'Autostart'. This keeps WhatsApp alive in the background so notifications arrive in real time. See how others solved this on Reddit

This usually means WhatsApp is being killed by memory management and lacks autostart permission. Go to Settings > Apps > Permissions > Autostart and toggle WhatsApp on, then open Recent apps, drag the WhatsApp card down and tap the lock icon so it isn't cleared. Also confirm Settings > Apps > Manage apps > WhatsApp > Notifications is enabled with sound and pop-ups allowed. See how others solved this on Reddit

System updates often reset battery and autostart settings back to restricted. Reapply them in Settings > Apps > Manage apps > WhatsApp by setting 'Battery saver' to 'No restrictions' and turning 'Autostart' back on. If the device is in a global power-saving mode, also check Settings > Battery and make sure Battery saver / Ultra battery saver isn't throttling background apps. See how others solved this on Reddit

Incoming calls need a high-priority notification channel plus the ability to run in the background. In WhatsApp go to Settings > Notifications and make sure call notifications are on, then in Settings > Apps > Manage apps > WhatsApp > Notifications confirm the 'Calls' category shows pop-up and sound. Finally set WhatsApp's 'Battery saver' to 'No restrictions' so the call alert can wake the screen even when the app is closed. See how others solved this on Reddit

Wearables only forward alerts the phone actually displays, so if the Mi Mix suppresses WhatsApp calls the band gets nothing. In the Mi Fitness / Wearables app, enable app notifications for WhatsApp, then on the phone allow WhatsApp's call notifications and set the app to 'No restrictions' under battery. If you use Do Not Disturb while connected, make sure WhatsApp is allowed to bypass it. See how others solved this on Reddit

Chinese MIUI/HyperOS builds ship without Google Play Services, which WhatsApp uses to push notifications. Install Google Play Services, the Play Store and the Services Framework (or run the Google installer included in the China ROM's Downloads folder), then reboot and sign back into WhatsApp. After that, grant WhatsApp Autostart and set 'Battery saver' to 'No restrictions' so the push connection stays alive. See how others solved this on Reddit