Some 2-Factor immediately texts disappear from messages

For some two factor authentication codes that are texted to me, they disappear from messages instantaneously. This has been going on for a few months, but doesn't happen for every two factor authentication code. It's a bit terrifying, because I'll see the text come in, but then go to look at it in messages and it will have just been deleted automatically. I don't share my Apple ID with anyone else. What's going on?