My hens stopped laying

[whatbeginsabetnotthat]

I have four one and a half year old hens. All of the sudden, two of them stopped laying completely, and one lays irregularly. I thought maybe they had clutches in the woods, but I locked them in the coop for a few days because I was gone and then came home to only five eggs, three layed by the same hen. They are still eating, drinking, sleeping fine, etc, but I can’t figure out what is wrong. Any thoughts??

 

[nuthatched]

Likely molting, mine are and it's about time for it at a year and a half.