My guess is that it is a collection agency. I only have one - US Cellular; and I refuse to pay it. There was no contract because I had my own Blackberry. But when I requested it to be shut off on the 15th of the month, I was told they could not shut it off until the 12th of the next month - the anniversary date. That was almost $100, and I said I am tired of being ripped off by the big guy. I wasn't planning on buying anything for a while, and they are the only BAD on my report; so I am keeping my money.
Type in the number and collections to see if it comes up.