Need help with negative test scenario.

Verizon has bundle choice of 3 products with $25 discount=123 for 3 products purchased there is a total of 5 products High speed internet, cable, VOIP, cell phone, LAN line. each are $50 so if you purchase 3 for 125 then add 2 cost is 200... Here is the problem I need example of negative case of if customer orders 5 products? description has been verify if $25 discount apply to 5 products do I need to change the description as well when I do the negative case... thanks alot this is my 2nd day only just this bundle scenario is different than regular case of going past certain criteria....