Definitely dsipute it with the credit agencies. What the above post says is true, the must respond in writing or remove it. If it is not removed for some reason then by law you must be given the contact information for the people that confirmed this is a debt you need pay. Then you can hoepfully get them to straighten it out.
I had a similar thing with Verizon. Note that I have NEVER had ANY service with Verizon. I had a $90 charge off from them. I think that is odd, especially in light of the "never having any Verizon services" thing. I dispute it and they say it is valid so I call the people to get the details. I sit on hold for 2 hours listening to David Bowie (UGH!) and then the system says "we are now closed, call again tomorrow", click, *dial tone*. I call again the next day, same story. I call again and push buttons until I get a human. I try to tell them I need info on this and before I can finish, I get routed back to David Bowie. See above for results. I try again. By now, I am willing to just pay the 90 bucks even if it is bogus so I can buy a house. I get lucky and speak to some form mammalian life form and say, "Look, I just need to know where to send a check for this........" Back to David Bowie. DAMN!
Well, before I figure it out, I get the mortgage and the house anyway. As far as I know it is still there.