Unfair billing charges

I have informed Cell C via numberous calls and email to please stop debiting my account as I was doing direct payments into their account. Every time I pay I call their call center to confirm receipt which they confirm and then they still debit me when the account status shows as paid. They have done this multiple times after receiving payment and are now still charging me for debit orders that fail when they were informed since May 2025 to stop debiting the account. I have asked on multiple occasions for the debit order to be cancelled and they still have not done this. They are now costing me 1000s in charges for returned debit orders and have now even cancelled my telephone line due to their incompetence. I call their call center and their staff asks me why I am being debited when I pay cash, surely a question they should be answering. I am with them for over 20 years and feel this is utterly disgusting service. I get told well just pay it and I fail to understand why I must pay for failed debit orders that they still put through when my account is on a paid status. Also my contract amount is R699 but every month I am billed R715. I would love to know why all these extra charges are added on because when we sign a contract we sign for a set amount. Now it seems due to their sly ways they can just add whatever charges they feel and the customers must just pay it. This is very disgusting service considering I have been a client of yours for over 20 years.