I have a buff orpington hen.. Shes been laying for a while! But she only lays in one specific box... BUT i have a broody hen in that box with babies and dont want to disturb things as some are in the process of hatching. The broody wont let the BO in the box (obviously) and the BO wont go in the other best boxes! Even when i out her in them manually! Ugh its so frustrating! I dont know why she wont go in the other boxes.
Hens usually like to lay where there are other eggs, so you can put some ping pong balls or eggs in the boxes you want her to go in and she might decide to. Maybe you can put her in the box you want her to go in too (my chicks didn't realize there was a roosting bar and nesting boxes to sleep in, in their coop, until I put them up there )
I agree with this and you can also use easter eggs filled with sand, if you don't want to use actual eggs