Terrible Telkom service

I have cancelled my Telkom service end of June 2017. I got a confirmation number that the case is closed. Case/Order Reference Number: ***1 . Now at the end of September I still receive my invoices, I still have to pay. Cancellation did not happen. When I query, they say a ISP is holding the line.

I find it ridiculous. I need to keep on paying, after I received confirmation that the service was cancelled. Now I have to give another 30 days notice. I want a refund and my service cancelled with immediate effect