WhatsApp for Samsung Galaxy On8

Open Settings > Apps > WhatsApp > Notifications and make sure the Calls notifications are turned on, then open the Calls category and set its importance so it pops on screen with sound. Also go to Settings > Apps > WhatsApp > Battery and choose Unrestricted, and turn off any battery saver under Settings > Battery and device care, since Samsung's power management often silences incoming call alerts when the app is in the background. See how others solved this on Reddit

This loop means your installed WhatsApp build has reached its expiry date and must be updated, so open the Play Store, search WhatsApp, and tap Update. If no update appears or it fails, download the latest APK from whatsapp.com/android, or uninstall and reinstall from the Play Store. If your clock is wrong, set Settings > General management > Date and time to Automatic, and clear the Play Store cache via Settings > Apps > Google Play Store > Storage > Clear cache before retrying. See how others solved this on Reddit

The On8 is an older entry-level phone, so close background apps from the recents screen to free up RAM before a call, and connect to Wi-Fi instead of mobile data when possible. Keep WhatsApp updated from the Play Store, since older versions handle the video codec less efficiently, and clear its cache under Settings > Apps > WhatsApp > Storage > Clear cache. Turning off the camera and switching to a voice call also reduces load when the connection is weak. See how others solved this on Reddit

Delayed notifications on Samsung phones are almost always caused by aggressive battery optimization, so set Settings > Apps > WhatsApp > Battery to Unrestricted. Then go to Settings > Battery and device care > Background usage limits and make sure WhatsApp is not in the Sleeping apps or Deep sleeping apps list, and turn off Adaptive battery. Keeping Wi-Fi on during sleep (in the advanced Wi-Fi settings) also helps notifications arrive on time. See how others solved this on Reddit

WhatsApp saves received media to your gallery by default, so open WhatsApp > Settings > Chats and turn off Media visibility to keep new images out of the gallery. To stop them downloading at all, go to WhatsApp > Settings > Storage and data > Media auto-download and clear photos, audio, video, and documents for mobile data, Wi-Fi, and roaming. See how others solved this on Reddit

Updates occasionally introduce bugs, so if WhatsApp acts up right after a system or app update, first clear its cache via Settings > Apps > WhatsApp > Storage > Clear cache and restart the phone before doing anything drastic. If problems persist, back up your chats via WhatsApp > Settings > Chats > Chat backup (to Google Drive), then uninstall and reinstall WhatsApp from the Play Store, which resolves most post-update glitches without losing your messages. See how others solved this on Reddit