Bartonsfinest
Songster
My two black sex links did the same thing for entire year, my gals only went inside the coop to lay eggs or if was two cold outside. My attached run was predator proof so I didn't make a big deal out of them not wanting to go inside the coop. If your girls are safe let them go. I don't think there is any underlining reason why they don't want to go inside the coop