Never ending impossible to get out of Contract with Cell C

Cell C has to be the worst provider I’ve ever had to deal with. I’d suggest people who want contracts to not even consider them. I’ve been having the same problem for the past two years of ClearScore reporting I am behind payment by R120 recently went up to R190 (the same amount I last paid on the account). I’ve tried to call Cell C a number of times to cancel the supposed contract which I know I finished 2 years or so back. I get transferred from this consultant to another I’ve even emailed them with no remedy to the situation. When I went into store was told my account was handed over and bought by a debt company for R38 and some change!!!! Meanwhile CELL C calls me every now and then selling me other products but had never called back to solve this issue. My credit score has been bad cause of them and I’m tired of it. I can’t do anything with a score like this!!! Please resolve!!