MTN is robbing me blind (double debit two months in a row just to cancel a contract)

I was double debited this month (on 28 February 2026). This happened again last month (January 2026) just because I initiated the contract cancellation for one of the numbers on my profile that I did not want an upgrade. Last month I was double debited R2340 after making a payment plan to pay 1/3 of my monthly installment of R2340 + (1/3* R2340) = R3120, and I was debited R2340 * 2 = R4680. The reason for the payment plan and the double debit was due to MTN's fault of cancelling my January 2026 debit order without my permission, which i was not aware of until i wanted to initiate the contract cancellation on one of my cellphone numbers on my profile. January 2026 was supposed to be my last month paying for the Samsung S23 Ultra device. The above mentioned issues have never happened before until my last payment month. After I had expressed my intentions to initiate the cancellation to all of the call centre representatives that called me (Linda being the last contact I spoke to), offering me upgrade options, of which I declined. I am starting to get really frustrated with your service as MTN and am not a happy client AT ALL. Kindly please fix this mess and stop debiting me from today onwards as my contract with you on the specified number is over and there was clear communication on stopping the upgrade process and converting the contract number to prepaid.