Telkom Cancellation ****

I had an ADSL line with them 3 years ago and cancelled it after a year after moving out of that apartment. I was charged for a few months for it after that and eventually stopped paying it. I have sent emails to no avail or answer. The line obviously hasn’t been used as I don’t live there. In any case, they have black listed me and this is negatively affected my credit score. Worst. Company. Ever.