MTN is a ****

I received a call from MTN Sales Agent offering me a simcard for Data...I received the simcard and realised the data is not what I wanted. I cancelled the contract on the 11 November 2021 after calling them several times. They promised to escalate the matter and not charge me cancelation fee because I cancelled the contract within 10 days of receiving it.i have received a couple of their response from different individuals asking different questions and telling me they have escalated the matter. MTN debited me +R500 in Nov 2021. They also debited me R299 but it bounced back in Dec 2021 ( I deliberately moved money from my account) they sent me a monthly statement today and it shows they will debit me R734.88 on the 25th Jan. I have tried to cancel this simcard but I'm failing to, every month the fee is increasing. I am being ********** and feel ****med.