Why offer a discount and have issues applying it on the account

I had an issue with my balance on the app last week I raised a complaint and it was fixed. On Saturday i went to multichoice dstv center and activated Xtra view then moving forward my balance was supposed to be R295 for Compact on promo until next year march, R99 for dstv access and R90 for Xtra view access fee in total it should be R484 and that's what i need to see on the app but instead i see R626.72 and when i ask I'm told that the was an error while applying the discount for dstv compact.

Please fix my balance on the app to be correct. I should see R484 not to be told to ignore the amount and stick to what i know i should pay Ref ********** 9