Cell c sucks

Cell c is the worst company I ever dealt within the history of making contracts.. I paid off my cell c account for almost 2 years but decided to settle it... I asked for a paid up letter since January when I paid up this damn account and they said it will take 48 hours.. Its 6 months now I've been asking for the same thing, I check my credit score.. There they are saying I owe them, after I asked teem nicely to close the damn accounts, they are all on prepaid so I don't know what the instalment is for... I will never recommend anyone to your company you are ********** ????