My parents said no at the last minute?

well at first, my mom said that i could go swimming with my friend natalie at this water park, then my dad came and we talked about it and they said "they never met or talked to the dad" and my dad saw natalies dad at a choir concert. today is the day me and natalie are supposed to be going swimming, and natalie still dosent know i cant go, shes gunna freak, any way i can get my parents to say yes?