There is a bug for those users with 0 free snipe credits, a $0 balance, and no credit card on file with us. Basically if you have no money or credit to snipe we should still let you add a snipe today because it's a free day. However it's not letting users in the case above do that. More info here:
https://community.auctionsniper.com/eve/forums/a/tpc/f/3...501091192#4501091192