Ridiculous cancellation process

I have been struggling to cancel my Telkom account for over a year and I am continuing to be billed for a service that I no longer require or utilise. The service from Telkom has been poor. I keep being referred to My Telkom which I am unable to login to, the system hangs, I have spent hours on the line with call centre agents, I have emailed agents directly yet I am still continuing to be billed. When I try put a stop order on my account I am unable to do so. this is ridiculous.