None-existent service

Telkom is without a doubt one of the worst companies I have had to deal with! 2 years ago I signed up for a landline and 10mb/s adsl line, the engineer came out and confirmed I could get 10mb/s unlimited and for the past 2 years I have been paying for this service and yet never had much above 6mb/s with any consistency! After several calls to Telkom customer service and visits from engineers (who by the way advised that I would never get 10mb/s or close to as I was too far away from the exchange and the ageing network would not support it) I am still not getting what I pay for and yet Telkom will not downgrade my line. Then late last year Telkom rolled out fibre in my area, the house below and next to me have access but I cannot get fibre, even though I signed up to be advised when fibre was available. Anyway, roll up April this year (26th to be exact), I call Telkom to advise we are moving house on the 16th of May and ask if it would be possible to have the move of my line and adsl done on the 16th (giving Telkom another chance to redeem themselves, thinking 3 weeks notice would be more than adequate) of May, the agent assured me this will be done and she will arrange with engineering. Needless to say, the 16th came and went and no word from Telkom. On the 18th I called to query and it appeared as if no one knew about the request, so I refer to my call of the 26th April and ask if they could assist me in the near future, only to be told that it would be a minimum of 3 weeks before they could help. So I thanked them for their service, NOT, and advised I would like to speak to someone to cancel my service, only to be told that I cannot speak with anyone and that I should use the self service portal to request a cancellation, which I duly did. A week later I get a call from Telkom engineering requesting information regarding to my move request, by which time I had already signed up with a different provider. I thought it strange receiving this call considering that I have requested a cancellation of my account, so proceeded to follow up on the cancellation. The agent advised that my cancellation was not processed as yet and would take up to 21 working days (over a month) to process, I explained the situation to her and demanded immediate cancellation as 1. we are no longer at the old address and 2. it was their mess that had led to the situation. The agent then proceeded to tell me that if I wanted to cancel immediately I would have to pay a cancellation fee. So my choices are pay an additional months fees for a service I could not use or pay the cancellation fee so that Telkom could do their work???!!! I asked to speak with a manager, at first I was told I could not speak with a manager (this I thought strange too, surely as a paying customer I have the right to speak with a manager should I wish to, especially considering that it was clear the agent did not have the knowledge nor authority to assist me?!), after insisting a few times I was told the manager was not available and was put through to a team leader who told me more of the same??!! Again I insisted and was yet again advised the manager does not take calls, then the manager was unavailable and then the manager was not in that day (well which is it??) and finally hung up. I have tried several times since to find someone within Telkom with the intelligence to understand the issue/situation and the authority to do something about it to no avail, I am at my whits end!