corporate headquarters address

I have a problem with my Direct TV billing. They are charging me for one additional receiver that I do not have. I have called Customer loyalty twice and they can't seem to figure out what equipment I have and don't have. The problem is that I've been billed $7.00/mo extra for approximately 32 months. The so called, customer loyalty representative was worthless and rather than solve the problem just made it worse. I would appreciate the name and contact information for the Customer Loyalty VP of both Direct TV and ATT.