Wrong information from Att/Frontier Communications on mailed letter

I received a letter from Att/Frontier communications in the mail. The letter to me didn't look right the envelope had a different name on it not mine but had my address. Then when I opened the letter it had the same company name on the inside with my address and said something about regarding your account and the account number looked like a landline account number but it was neither mine or the wrong name on the letter or envelope. Something doesnt seem right to me on letter from ATT/Frontier and three pieces of information don't match it was my address not my name and somebody elses account number...the letter was dated Sept 18 and the envelope looked like a piece of junk mail at first. The letter described the changes coming up with Frontier didn't have a problem with that. The letter head also had the att logo on it and had Frontiers name on it also.

So I was wondering if anyone had gotton and mail in the past few days that seems to have information that doesn't add up. Thanks