How to retrieve deleted text messages
How do I retrieve deleted text messages
iPhone 12, iOS 14
Go to Settings > (Your Name) > iCloud > Messages. If it is turned on then you activated iCloud Messaging and your text messages are gone.
If it is off, and your text messages are contained in your most recent backup, restore your iPhone from that backup. You will lose any data added since the time/date of that backup.
Restore your iPhone, iPad, or iPod touch from a backup - Apple Support