T-mobile USA, Inc. Billed for cancellation fee when there was no purchase of cell and contract was expired. Albuquerque New Mexico

This account was closed about two months ago due to the bad service reception at my home.  I have not bought any mobile device since 2010 and therefore have not renewed any contract.  I have been their "loyal" customer since 2003 and have always kept my account to date. I have been receiving a contract cancellation bill of $299.00 which is not valid. When I call to dispute the charges, T-mobile tells me that the contract was renewed by "?". I called three different times and each time they tell me a different story as to why I am being billed. I believe they have renewed my contract on purpose to force customers (including myself) to pay such high cancellation fees. I believe this unlawful and someone needs to stop this!