Check the Recently Deleted folder in Messages
Open Messages
Tap Edit or Filters
Tap Show Recently Deleted
Select the messages you want
Tap Recover
Restore from an iCloud backup
Go to Settings
Tap General
Tap Transfer or Reset iPhone
Tap Erase All Content and Settings
Set up your iPhone again
Choose Restore from iCloud Backup during setup
Restore from a computer backup
Connect your iPhone to a Mac or PC
Open Finder or iTunes
Select your iPhone
Choose Restore Backup
Check Messages on other Apple devices
Look on your iPad or Mac if Messages in iCloud is enabled
Contact your carrier
Ask if they can provide message records
Use a third-party recovery tool
Install a trusted recovery app or software
Scan your iPhone or backup for deleted messages