Struggling to cancel Showmax

I cancelled my Showmax subscription via Telkom on the 1st of March by filling in a form which I was informed I need to fill by telkom customer care. The form was sent to ********** . The subscription was not cancelled as my account was still being debited. I called Telkom again in May and spoke to someone who gave an email address ********** I sent an email to the above address on the 3rd of May and again in June. The last email in June could not be delivered to the same address. My account is still being debited to date as Telkom has failed to cancel the subscription. The case number that was provided when I called is ********** 0. I need my full refund from March 2018 to date.