Poor service from Telkom

I have had such a bad experience with Telkom. In 2021 I signed up for a Telkom sim where I would get data and I had to pay about R200 which is fine. I was told when signing up that it was prepaid which meant I could lad cancel the subscription anytime but when I wanted to cancel it I was told that there was fees I would have to pay as it was not prepaid. To which I was like it’s fine cancel it but after that I was charged extra which I thought mabye agent accidentally done this cancellation and I was fine with it. Months went by but than for some reason money would get taken out of my account and they labelled it as that I hadn’t paid my subscriptions I was being charged R1000s and many more when I wrote to them they said I must send email with proof which I did but never got response. I was put in debt review recently I am getting called asking for payout and I explained this and they haven’t done anything so I am very disappointed by Telkom as they are ruining my credit score and I don’t know what to do anymore