Being forced to continue with service!!!!

I've never received good service from Telkom, ever since I've been their customer. I have a sim card contract with them, first of all they didn't inform me about the contract ending, I kept paying. I've been calling them for two months already to cancel my subscription, with no success, I even went to their site where you can request cancellation, still nothing, I then decided to reverse the debit order for two months and now I'm receiving threats that I'll be listed on the credit bureau, their store turned me back when I went to cancel, they told me to call their call centre, I did, instead that phone never goes through... I would never recommend Telkom to anyone, even after seeing this, I'm 100% sure they won't call. They don't even deserve one star, just a zero