Not sure how old your chickens are, but they will molt unless you are trying to stop them with the light. I opted out of lighting my coop, my girls have a couple of good years of laying well and I did not want to stop the molt, and I wanted them to lay longer in there life then have them force lay with all the light. Funny thing was, out of my five birds, I got eggs from them all after they molted. It was a light molt, and with in 6 weeks everyone of them laid eggs. YEah some days only 2 out of 5 laid but hey that's over a dozen a week and fine as we have big breakfasts on the weekends