Telkom useless at closing an account 8 months after it should have been cancelled

No one at Telkom can assist me. Every month I call to complain that I still get invoices from them on an account that should have been closed in January. And every month they keep sending me an invoice and taking money from my account. I just spent 10 minutes on the call with them now and the agent cut the call because she could not help me. This is the worst service ever.