gambler104: Well that is the reason why it will not allow him to change it - since people signed up thinking it was going to be one thing. To be fair to everyone, either (1) prize that was offered needs to be awarded or (2) delete tournament, and create a new one with the new prize.

You can't start a tournament and say you will give the winner $1,000 - then later say "Oh, changed my mind - here is a $1.00 instead) (of course this is an "extreme" example, but hopefully shows the point of why it should not be changed)