Telkom the steel money

I cancelled my ADSL service with telkom in August and was advised it will take 20 days for cancellation to take effect, they advised I will be billed only once more, I have now received another invoice for over R600 that will be debited out of my account the end of October. Telkom could not provide me with the service I needed at my new residence, now I have a new ISP and have to pay both telkom and my new ISP, this is ridiculous and I contacted telkom 5 times yet the only thing the billing agents tell me is they will log a dispute, telkom needs to e put out of business, their agents are *********** and their service sucks. I wish someone would put telkom out of business cause anyone else would be able to do a better job than these people. We log reviews to be assisted but they dont care to even respond to their paying clients. We pay for a service and get nothing in return, They also want you to contact them to get your own money back. telkom are a bunch of theaves and need to be locked up.