Account linked to user several states over

Has anyone had their account linked to someone it should not be linked to?   I received an email tonight, after asking that my old and new accounts be linked, from someone in Florida letting me know that my account was now linked to theirs.  I am in Virginia.

Called Comcast  - who told me it was spam but there was problems with my account and they were esculating it.  Person confirmed serveral items of info that you could find on my account (not internet).

Can not get hold of a live person.   Comcast site will not allow deletion of credit card.  Concerned about my personal information.

C