Check the Recently Deleted folder in the Messages app
Open Messages
Tap Edit or Filters
Select Recently Deleted
Choose the messages you want to restore
Tap Recover
Restore from an iCloud backup
Go to Settings
Tap your name
Tap iCloud
Tap iCloud Backup
Confirm you have a backup from before the messages were deleted
Erase your iPhone
During setup, choose Restore from iCloud Backup
Select the relevant backup
Restore from a Mac backup
Connect your iPhone to your Mac
Open Finder on macOS Catalina or later
Open iTunes on older macOS versions
Select your device
Choose Restore Backup
Pick a backup made before deletion
Restore from an archived backup on a computer
Use Finder or iTunes
Select the device backup
Restore the backup that contains the deleted iMessages
Check other Apple devices
Open Messages on your iPad, Mac, or another iPhone
See whether the deleted iMessages are still available there
Turn on Messages in iCloud if needed to sync
Contact your carrier if the messages were SMS or MMS
Ask whether message records or backups are available
Request any supported recovery options
Use third-party recovery software
Connect your iPhone to a computer
Scan for deleted messages with a trusted recovery tool
Recover only if the tool supports iMessage retrieval
Prevent future loss
Turn on Messages in iCloud
Create regular iCloud or computer backups
Keep backups before deleting important messages