Telkom line rental cancellation

After sending cancellation letters via email every month since September 2021 to cancel a line rental, i am still being charged. With all this Im having Blake and Associates phoning me 5-6 times a day asking to confirm my date of birth before they can speak to me. Wth? According to them I should settle the account and only then will i be able to cancel the line rental. If they canceled the line in September as per cancellation request there would not have been any account outstanding. So who is in default here? Telkom seems to ignore cancellation requests to try and pocket more and do not even try to communicate before handing the account over to Blake and Associates. When trying to phone them they tell you to phone telkom to make arrangements- these 2 companies are the worst I’ve ever had to deal with- *********** to the core.