Still being billed after cancelling service

I cancelled my Telkom line when I left KZN on the 26th of June 2017. I then received a bill and so tried to cancel online. There is no function on the website to achieve this, so I called to cancel (again). I was unable to cancel telephonically and was sent a form to print (in this day and age!), complete, and send back. I did so, and received no response whatsoever. I have just been billed for another month's use, despite not having a phone line since end June. The new bill is - magically - over R1200, despite the fact that is has not been used since it does not exist anymore.