This. Two nights is not enough. Somewhere between four nights and a week should do it. Do this right at dusk when there's still just enough light for them to see. If the coop is too dark for them to see into, they won't go in by themselves, they don't see well in darkness. If it has windows, they should do okay. Good luck!Go out BEFORE it is totally dark. Put them on the roost and roost them in the same spot (each bird) every night. As soon as you get them on the roost lock up. Might take a couple of days for them to go in or a week even. Birds develop habits pretty quickly.