How do you get sunset beach in mario hoops?

i did what everyone told me to do. play between 4-6 PM on koopa beach and win. i know. i got 500 and it still didnt let be get sunst beach! i even changed the time on my ds, played koopa beach again, won, and i still didnt get it. im thinking its a scam. there must be something im doing wrong! do i have 2 be some certain character? do i have 2 adjust my settings? whats up with that?|||http://www.gamefaqs.com/portable/ds/game鈥?/a>