Out of nowhere about fifty contacts appears on my contact list!!! When I went to delete them I got a message since they were message contacts, not phone I could hide them but they would remain. WTH???
In Contacts, hit the ellipsis (3 dots) at the top right. Hit “Contacts to display”, and go to customize. You should see one or more accounts in there. You can expand each account, and toggle checkboxes 1 at a time to see what’s bringing in the “mysterious” contacts.
You can also try editing a “mysterious” contact and hitting “More fields”. This should then show you what account the contact is for.