To cancel a subscription on Cell C, simply dial the USSD code *133*1#. This code will also block future unauthorised subscriptions or billings.
To check subscriptions on Cell C, open the App, select “More” at the bottom right, and then select “Content Services”. You will see a list of your active subscriptions or “You’re not subscribed to any content services”. To block your number, use the button at the bottom of the screen which says “Block content services”.