You cannot directly view deleted WhatsApp messages inside WhatsApp after they are removed
Check your phone’s notification history if it was enabled before the message was deleted
On Android, use Notification History or notification log features if available on your device
On iPhone, check any notification previews that may still be visible on the lock screen or Notification Center
Restore WhatsApp from a cloud backup made before the message was deleted
On Android, restore from Google Drive backup if available
On iPhone, restore from iCloud backup if available
Check any linked devices if the message was shown there before deletion
Use third-party notification saver apps only if you already had them installed before the message was deleted
Ask the sender to resend the message
Check exported chat backups if you previously saved the conversation