Frustrated customer

Hi. I cancelled my telkom line in March. Every month I get charged. I had received a letter that it was cancelled, yet monthly, 2022. Each month I get an account. Monthly I phone the accounts department and each month a different person promises to sort it out. They send the email to the cancellation department who does nothing about it. This is now September, 2022. I cannot reach the ombudsman. What am I supposed to do?