Billed Incorrectly

I have closed my Cell C contract Accounts and I am not owing anything. Cell C has handed me over to their Legal Department. I went to one of the Cell C stores to sort out this matter, I was advised to email their credit department which I have and still no response from Cell C . The turnaround time for a reply is 48 Hours . But still no response .

Can Cell C fix this issue ASAP.