If I'm on commission with draw..?

can they force you to stay past closing or come in before opening the store when there is absolutely no way you can sale to someone and therefore losing money out of your paycheck? Is that legal? I live in Nevada, by the way. I've done commission for a long time and did draw/commission a long time ago but was never forced to stay when there's not a way to make any commission. Oh and they refused to give me non-productive hours. Any ideas on the legality. Thanks!