IPhone sent a text message, accidentally entered letters in the recipient field, and some strange names and numbers appeared. Where did this come from? besides

These names are all in your address book. It is possible that your mobile phone and another mobile phone used the same APP ID, and then both of them saved their address books in the cloud service center recommended by Apple. After the address book is restored, the address book from another mobile phone will be downloaded to your mobile phone. I've been in this situation, too ...