Contract cancellation

I had a Vodacom contract which was due to expire in Jan 2021. As I use an MTN sim I couldn't reach the call center directly and used my colleagues phones' instead. I first calling in Oct 2020 to give notice of cancellation. They sent a form through to me which I completed and returned with an ID copy twice. The line wasn't cancelled as it was apparently the wrong form that the consultant sent. Since January they charged R175pm and each time I called again to complain. Each time the consultant promised that the line will be cancelled and the charges refunded. Each time it's one hellish struggle to even get the consultant to promise to cancel as the "retentions" department keeps trying to push a new contract. They still didn't cancel the contract. I resorted to have the debit orders reversed. for the last two months. Now Vodacom is trying to collect these amounts despite them being instructed to cancel months in advance. I can provide Vodacom with the numbers I called from but once again when given to a consultant they always have a story why they cant search for the recordings. I also tried going into the branch, but once again they couldn't help as they don't have 'access' to that system. Every step of the way has been nightmare dealing with Vodacom staff having a don't know, don't care attitude.