They "catch" the message the moment it arrives and save a copy in their own database.
To view messages that a sender has deleted on WhatsApp, you generally have to rely on logs that captured the message before it was removed. While WhatsApp does not have an official "undelete" feature, several workarounds exist depending on your device. 📱 Android Methods whatsdelete-view-deleted-messages
Uninstall WhatsApp and reinstall it from the App Store . They "catch" the message the moment it arrives
If you have Android 11 or newer, you can often view deleted texts without any extra apps. Go to Settings > Notifications > Notification History . Toggle it On to see a log of incoming messages. whatsdelete-view-deleted-messages