Ludicrous amount of my for April debit order ?? On payment plan???

Please could someone at DSTV explain why you reckon I owe you R3149.79? My payment plan is R959 per month. Last month you debited me with R1145.00, I reversed the debit order because this is not the amount agreed apon. Hoping that you would rectify this month and double debit me with 959 x 2 plus the R70.00 for box office which = R1988.00. To my horror, I log on and see that you will be taking R3149.79 from my account. Please explain where you get your figures from??? I will be stopping the debit and will pay you the R1988.00 that I am supposed to pay. Not a cent more. Sort your **** out dstv