Showmax automatically charges you if you downgrade from premium DSTV - no warning

I was previously on DSTV premium where I received Showmax for free. Unbeknown to me, when I downgraded my package to compact, Showmax started billing me for R99 per month without any notification. There was not any notification from DSTV either and only when going into my detailed DSTV billing did I pick up the Showmax fee. Strangely, compact customers are only supposed to pay R49 a month on Showmax, but they charged R99. They will not refund my money as they say I didn't cancel Showmax. So beware anyone who is downgrading their DSTV from Premium to cancel Showmax immediately or you will be charged full fees. I am still trying to get them to refund my R50 that they overcharged - have had to submit my dstv accounts to prove that I was on compact and not premium.