Dealing with Telkom has given me PTSD

I have attempted to cancel my Telkom account multiple times since June 2018. I estimate I have been into the branches 5 times, attempted to cancel online multiple times, phoned numerous times. I have written proof from the Rosebank Telkom branch staff on the 1st of July 2018 that my account would be cancelled. It was not.

I have now been handed over for debt collection for the monthly subscription fee which has accumulated since I cancelled my account. The debt collector assures me that if I just pay the outstanding amount and fill in a form, which I have previously filled in., then it will be cancelled. I know this is not true due to the below:

If I manage to speak to anyone at Telkom with any actual answers, they tell me they cannot cancel my line as there is an incomplete order on the line, however they cannot cancel the order, as there is a fault on the order and only IT can fix, however I cannot speak to IT directly and all I can do is log a call, which they then cancel as "resolved" with no communication with me. Its been a year.

I have no option ever of dealing with someone who can actually resolve this and cancel my account. I just want to get free from this toxic, *********** company.