how to restore deleted text messages to iphone

Restore your latest backup. There's no other way to recover your deleted messages.

You may find this website useful.

Restore your iPhone, iPad, or iPod touch from a backup - Apple Support

To restore text messages you have to restore from a back up that was made before they were deleted. Thats the only way to restore them.

If you had backed up the text messages with iCloud or iTunes before they were deleted, try to extract the messages from the backup and restore to your iPhone.