Convince My Parents to let me go to Sleepaway Camp... Someone help plzz.!?

Okay My Mom And Dad Signed Me Up For Sleepaway camp....it's the night before i need to go and now they're saying we dont know and were not feeling good about it and no youre not going??? my parents always...I MEAN ALWAYS have this last minute thing like youre gonna go and day before Nope sorry.... we'll make it up to you never happens im sick of thiss.... plz give me ways to convince them FASTTTT!!!