cell placed me on credit beuro

Cell c placed me on credit bureau and on collection for an account that I have been paying ever since i had a contract with them. I made payment on the 20th 12/2015 they keep allocating the funds to a wrong account as we speek my phone is off but i paid them way on time, as for their staff member at greenacres branch called Ben he is very rud.that shows how *********** they are, they say I have two account of which one is active and the other one is closed but the funds are always allocated to the closed acc . I want my name to off the credit bureau and all extra charges I incurred due to this error be reverse d with immediate effect