It seems if a random person calls virgin media and tells them no one is living at your address, you will be disconnected without notice and your account will get a fraud marker on it. They are happy however to continue collecting DD payments. Your account will also be passed to Collections which possibly could end with a default notice on your credit file.
I cannot fathom why a random person would be allowed to talk about anyone else's account without clearing security.
When trying to resolve the issue be prepared to spend a minimum of 5 hours with extremely defensive call centre staff who in the end are unable to help. Good luck!