Nuthatched may be right about it being an overbite. You could put a large rock inside her brooder and a bigger one later for her to brush her beak on to keep it worn down. Chickens usually ‘wipe’ their beaks after they eat. I don’t think that I would trim or file it down because she is too young.
Make sure that she is getting enough food, and you can weigh her on a kitchen gram scales to keep tract of it. Wetting a small amount of the feed in a little bowl may make it easier to eat if she is having problems.