MTN Monthly Contract Cancelled, still being debited!!!

Monthly MTN cell phone contract was cancelled in July 2021 and sent follow up emails. Stop payment was placed on debit order R259 but MTN change the amount each month now therefore the stop payment is no longer working and I am getting charged R48 each time to have the bank unpay the debit order. I was a customer of MTN for over 20 years, very disappointed by the service!!! I have emailed Customer Services and they respond 1 MONTH later requesting more info each time and continue to change the amount on the debit order, this is the way you rip your customers off. MTN YOU ARE *****ENTLY TAKING MONEY FROM MY BANK ACCOUNT AND I DO NOT HAVE A CONTRACT WITH YOU ANYMORE!