MTN penalised me for their agents not cancelling the contract I want my money

<p class="MsoNormal">Today I received the refund of R244 from MTN of which they debited +- R600 from my bank account from January until May 2016. I called and sent a letter to MTN notifying them that I will not upgrade and continue my services with them. MTN still decided to debit my bank account. I phoned every month from January 2016 until April 2016 to make sure that this is actioned accordingly, but without any satisfaction from MTN. I decided to place MTN on Hellopeter on the 18^th of April and on the 19^th of April I received a reply from MTN that they will process a refund within the next 7 days. May I logged another query as I still received nothing from MTN and the nerve they debited my bank account again. I notified them and their response was my account was charged a late cancellation fee. OMW I am being penalised and paying for the mistakes of the *********** agents working for MTN. I am paying for them being stupid. I am paying for them not doing their job. Please make sure that I get all my money that MTN stole for those months, not what MTN feels they want to give me back.</p>