Cell c contract

Buying a contract fone at cell c its nonsense you know,I had a contract with them for 2years and after two years they kept on debiting I didn't have a problem with that because anyway I was still getting their service,then yesterday some stupid idiot calls me from some attorney's and says I am owing cell c R1500 that money is For what,don't come here with your craziness,and I wanted to renew the contract I won't do that you guys must go to hell is this the way you treat your customers imagine your account has been handed over for being faithful to cell c,see if this matter is not going to be resolved today I don't know what's gonna happen