Not all discount on Vitality booking.

I used my discovery credit card to book accommodation. I am on diamond status so I should get 35 percent plus the 15 percent discount for using my discovery credit card.. Only the 35 percent discount was given. I phoned them and a call was logged about a week ago. ( #***)<br> Today I spoke to a lady ( #*** ) about this query and she told be the query was closed. Nobody contacted me.<br> Apparently I selected the wrong option on the screen when I made my booking. I selected VISA and not discovery credit card. I cannot remember because I did this a while ago. The payment went off my discovery credit card so as far as I know I paid with my discovery credit card. Surely they must know I used my discovery credit card and not another VISA card. I mean it is the same company. The fact of the matter is that I used my discovery credit card so I should get the additional discount..