R483pm for a 2Gb mobile data contract + Extend contract 2 years when requested to terminate

I've entered into an agreement with Vodacom about two years ago where I got a mobile data contract for R483pm. Yes, I know, that's ridiculously high, but that's not the point... I've been advised by my husband that this is way too high to pay monthly for 2Gb, as you can get the same amount of data on Top-Up for R249 (and that's not even on a fixed contract which would decrease the amount even more). I was not aware of the outrageous price this was when I first entered into the agreement, and only realised it later on. But as you all know, Vodacom closes a 2 year contract with you, which is basically impossible to terminate before expiry date, without having to sell an organ or two to afford the cancellation fees.

I've therefore waited and paid the 2 year contract, patiently, until the expiration date finally arrived!!! Then, I went into the shop to cancel the contract (because it automatically renews on a monthly basis if you don't expressly cancel it), only to find out that I must call a contact center to do this. So I went home and called, and requested that the contract be cancelled (This was beginning of November 2017 - also the expiry date of the contract). BUT, typically sales consultants, they convinced me to remain their client and enter into a new contract with them, for the same amount of data, but with a much lower monthly premium (I don't remember the amount, but it was definitely much lower - Vodacom doesn't send me a written contract to substantiate our oral agreement, nor informs me of the 1000 clauses that they don't mention over the phone, but that's probably just me???).

Now for the fun part... I am still paying the R483pm, three months later... I've called their customer query line, and thought I was successful when they said they will look into it and cancel the contract. But, even after receiving an sms on 24 January 2018 stating that the query has been closed, I still pay the R483pm. They don't mention the outcome of the query or the decision or anything else that's actually important to me, their client. No, they just do what they want and charge you what they want! I don't know what to do anymore. I don't have the time, nor the money to keep on playing this game.

If I knew that nothing bad would come from it, I'd stop the debit order, but as we all know, that will give them grounds to blacklist me (even though they are in the wrong). And I don't have the strength for legal battles over their arrogant actions.

I would probably be satisfied with proper communication from this communications giant, but all I get is bad service and a black hole in my bank account.