Cannot disconnect Showmax and keep getting charged

So besides being cut off in Feb for account non-payment when my account was actually in credit (even after apologies and reconnecting I have chosen to stay disconnected and get my viewing pleasure from another service provider) they are taking money off for Showmax. I never paid for showmax as I was premium subscriber but as it turns out when you cancel DSTV they don't cancel your Showmax (even though linked to your DSTV) and they don't inform you of this. I have been trying for over a month now to cancel my showmax but to no avail. I was credited for the payments that have been taken off since disconnection last week but again now for this month the Showmax has been charged. I keep being told I have to do this myself but as I have told everyone I have contacted I cannot do this because on the system it is "greyed out" where it states request cancellation and its states free service. The online chat feedback I get is that there is a technical problem in performing this function and it will be escalated but I get no feedback and I keep being charged. Totally unacceptable. How can I de-register from Showmax?