impossible to cancel- Stay away from telkom if you care about your credit record

Last year telkom billed me twice and i complained about the matter since the customer care was useless and kept telling me to email *** and submit proof, this issue has not been resolved. I have went on to request for cancellation instead they continue to debit my account every month and when i reverse the debit order they threaten to have their lawyers come after me, the same lawyers i emailed and explained the situation to, those same lawyers did even respond, to top it off they threaten my credit record. I am so sick of telkom. i have been calling their call center and they are taking me from pillar to post.