Urgently correct and reverse my money.

This my second request. I am not sure if this helps. I have a data plan that I was told it'll be R270 monthly. But the debit is R520. Whenever I call 135 to cancel the phone gets cut off. Please cancel this. I was on a plan that I was paying R299 for the past 2 years. Upon upgrade I downgraded to 70Gig. I was told it's black Friday deal. Which I will pay R270. I want you to rectify this and reverse what you have been debiting wrongly. ***...is data Sim. My contact details is ***