Ripping customer off & BAD SERVICE

Dstv is ripping us off, they changed my subscription to DSTV premier whereas I subscribed for R519 service, now to my surprise they disconnected my services and according to them I owe R1260, No one can explain how it got to that amount, tried calling 5 times today instead they hang up on me. I need my services to be connected or cancel the dstv for good.