Bring billed for Prime Video subscription, after I called to cancel

I was offered a free 3 month subscription to Prime Video. Before the 3 months was up I called Telkom to please cancel this as I did not want to be billed, once the three months was up. Today I get am sis to state that my subscription for Orine Video was automaticallt renewed and that I have been billed R79. Trying to call the client care is a nightmare, when I did eventually get soak to someone, they said they transferring me to billing, then my call eventually got cut.