WhatsApp for Xiaomi 11 Lite 5G

This is MIUI/HyperOS aggressively closing WhatsApp in the background to save battery. Go to Settings > Apps > Manage apps > WhatsApp, set Battery saver to No restrictions, and turn on Autostart. Then open the recents screen (swipe up and hold), and lock WhatsApp by tapping the lock icon (or swiping down on the card) so the system keeps it running. This combination is what reliably restores instant notifications. See how others solved this on Reddit

WhatsApp blocks running as a MIUI Dual App because the cloned copy is treated as a modified/unofficial client, so it refuses to register. The reliable workaround is to install WhatsApp Business from the Play Store as your second number, since it is a separate official app and can run alongside standard WhatsApp. Newer WhatsApp versions also support adding a second account natively under Settings > tap the arrow next to your name > Add account, which avoids Dual Apps entirely. See how others solved this on Reddit

MIUI/HyperOS restricts which apps can wake the screen, so incoming calls get suppressed. Go to Settings > Apps > Manage apps > WhatsApp > Other permissions and enable 'Display pop-up windows while running in the background' and 'Show on lock screen'. Also set WhatsApp to No restrictions under Battery saver and turn on Autostart so it can ring even when the phone is idle. See how others solved this on Reddit

This is a proximity sensor issue that is common on the Mi 11 Lite 5G, often appearing after an update. Open the MIUI hardware test by dialing *#*#6484#*#* and run the proximity sensor test to confirm and recalibrate it. Make sure no screen protector or dirt covers the sensor area near the earpiece, since that is the most frequent cause. If it persists, clear WhatsApp's cache via Settings > Apps > Manage apps > WhatsApp > Clear data > Clear cache (this does not delete your chats). See how others solved this on Reddit

This usually happens when no app is set to handle PDFs. Install a dedicated reader such as Adobe Acrobat or Google Drive from the Play Store, then tap the PDF in WhatsApp and, when asked which app to open it with, choose the reader and select Always. If you are not prompted, open the file from the Files app instead and pick the reader there to set it as the default PDF handler. See how others solved this on Reddit

Update-related WhatsApp bugs are usually fixed by clearing the app cache and updating WhatsApp. Go to Settings > Apps > Manage apps > WhatsApp > Clear data > Clear cache (do not use 'Clear all data', which removes local chats), then update WhatsApp in the Play Store. If it still misbehaves, back up your chats first via WhatsApp Settings > Chats > Chat backup, then uninstall and reinstall the app. See how others solved this on Reddit