Portfolio Services / Sears Gold Mastercard un-notified of 164.00 owed to portfolio under my name from an old credit card now two years later it's balance is ruining my credit and growing why wasn't i told! Norfolk Virginia

I made the mistake of getting a credit card with sears gold mastercard. I pay my bills on time and on occasion I will pay late but never more than 30 days. At some point in the past 4 years my credit card sent a portion of my credit balance to portfolio services without notifying me. i was never told by portfolio nor was i told by mastercard. now portfolio is contacting me daily to resolve this it has been accumulating for years and hitting my credit they won't tell me what its for, they are very difficult to deal with. my credit card has no idea what its for how do i deal with this? it seams so fishy.

Sean
salt lake, Utah
U.S.A.