Disgusting treatment from Telkom customer service

In April for some reason, Telkom's debit order did not go off even though there was more than enough money in my account. A week went by and then I started receiving sms's that I did not make payment for the month. I then paid in the outstanding amount then thought while I'm at it I'll pay for the next month as well to make sure there are no issues with the next month's debit and since its way before the 5 days until the next debit, it should be reflected by then. It reflected on my new invoice but Telkom decided to debit me anyway even though I had already paid the amount. I reversed the money then started getting threatening messages of attorneys collecting and it affecting my credit score. I called in to say I have paid and that there is some kind of mistake, the agent confirmed that I have indeed made payment and the mistake is on their end and it will be corrected. 2 days pass and I started receiving the same sms's again and had my account suspended. I called in again and had the agent respond to me with an attitude trying to convince me that I am wrong, then upon seeing that the mistake was on their end, instead of apologizing she asks to place me on hold and then dropped the call forcing me to call in again and explain to yet another agent what the problem is, given the same answer that it will be resolved. As a long-time customer of Telkom, to receive harassing sms's for a fault on their end is extremely disgusting and unacceptable. I hope this problem gets resolved. If any Telkom heads read this, the name of the last agent to help me is Ntokozo Rose-Ann Mbuyazi and the manager's name is Lungi Cele.