No Customer Service from Telkom

I have been having a ongoing struggle getting a account that I have cancelled 11 December 2015 cancelled. Every Month Telkom still takes my Debit order. I have tried everything - Emailed them, phoned, went to the Head office at 92 Oak Street, Highveld, Centurion - Still nothing has been done - They have handed me over to Debt collectors that phoned me and when I sent all my proof to them they said that I am not at fault and that Telkom needs to do their part - Telkom even listed me as a bad payer because they can't seem to do their work. I have been emailing Shawn Makolah, Bianca Delo and the Cancellations department - But never get any response for anybody. When I went to the Head Office on 20 April 2016 - Shawn Makolah sent a email to Killandran Govender to please cancel my contract (As per the advice from Telkom Centurion Mall Branch) but still nothing has been done - They need to credit all money due as I have sent them all relevant paperwork that I have cancelled my account already on 11 December 2015 - As I had very bad signal - Centurion Mall branch advise me to cancel and then I took out a ADSL service which I am very happy with. I now must just get this account cancelled and my account credited accordingly. How can they debit my account every month for a cancelled service and when I try and sort this out I get absolutely no response (I see this as *****ing my money) Every time I have to go into the bank to reverse my Debit order - Can someone please help to get this sorted out - It is the worst service ever.