Cell C
Keep on billing me

I had a contract with Cell C that I cancelled after a lot of fighting with Cell C.
Now that it has been cancelled they still keep on deducting money from my account.
I had to reverse the transactions now for the last 2 months (9 times).
Please can some one help me put a end to this, as I have to take time of work every time to reverse the transaction and its getting really tedious.

Regards Brandt Els