Billing issues with multichoice

We are awarded rewards on their rewards app, where it says ugrage on us for a month or 2. Then the next thing when you claim. After a month or 2 your being charged for it. They upgrade your subscription without your permission. Right now I'm faced with a bill of 1543 which it occurred because, I claimed the reward then insisted they downgrade my subscription. Then I was charged 1200 in June which I queried then they refunded me. Last month my account was back to normal now this month I'm being charged my normal subscription and the refund they refunded. What ki d of billing system is Multichoice using? I'm frustrated because I can't afford this bill on the 1st of August 2021