How to cancel Showmax account billed through Telkom

cannot cancel showmax subscription billed through telkom. I contacted telkom to cancel showmax but could not assist and told me to phone showmax as they could not cancel. Showmax told me the same that they could not cancel. How do I cancel my showmax account which is billed through telkom. I have been sent from pillar to post and neither telkom nor showmax can cancel my subscription.