I have five RIR hens, four are young, but one is over a year old and very healthy. The older hen is the first I got, she was laying eggs at the place I got her from, but not a single one for me. The coop has a large window that allows the sun to shine through out the day, and a light that is on for 3 more hrs at dusk. They have clean straw, a warm coop, great food, they are in a quite area, have pleanty of light, plenty of clean water, everything to the best of knowledge they need. Is there something I'm missing?