Telkom no customer service

Telkom has the worst service. I phoned again and insisted to speak to a manager. The consultant said it’s not possible to put me through and she’ll get a manager to call me back. More than a week no response… I received a message today from their attorneys (p&p attorneys) which I also mailed all the proof and also no response except for threats, that I need to pay my bill. I phoned again and spoke to one of the billing consultants which informed me my cancellation was processed on Oct and that was the reason why I was billed but I have the proof that my cancellation was done in May. Why do I need to pay for a service I haven’t used and how is it possible that it takes 6 months just to cancel a service??