Showmax charging on canceled subscription

I would like multichoice to rectify my account I canceled my showmax subscription on the 12 of August but I see my Dstv account has been charged with the amount again and I received a notification that it will be canceled on the 22nd of August and I won't be charged know I need to pay for something I canceled. Can I get assistance on my account being rectified because than it's ***** if they subscribe you again without your knowledge