Vodacom, Just cancel my contract!!!

Absolutely disgusted with how Vodacom is dealing with cancellations. My contract came to an end on the 1st of June 2022, I called on the 31st of May to cancel. I wanted to move my numbers over to prepayment. I know I had to call the 1st of May but I was okay with paying an extra month. I then got through to a retentions advisor who sold me a sim only deal for both numbers which I agreed to. I then called in a few minutes later to cancel that deal I just want to cancel the new deal before it all went through. The advisor told me that it was already put through and cannot cancel it now. You have a 14 day cool off period! I want the cancel. Now I am being told that a cancellation form was sent through and it will only cancel at the end of the month and then it will revert back to my old deal then only I can cancel and move my numbers over to prepay. So now I have to pay for my old contract and my new contract.

Why can't I just cancel? And move on with my life and pay the final installment. Why does it have to be so difficult?