Telkom connect is busy ****ming people of South Africa

This Telkom is not good at all it's actually a **** I have a contract sim card with them which I was supposed to pay R260 every month according to our agreement,but nou they are debiting R550 every month which is not our agreement So when I call them to cancel my contract, they refuses,So what must I do with such ****s I need my extra money that they took from my account or else I will change the bank account number This Telkom company is not good at all and I think Leitlho la Sechaba need to pay attention on them