I have two gold comets that started laying in August. They are free range and I have been giving them layer crumble. The first two dozen eggs have been perfect but now all i'm getting are soft shelled and no shelled eggs. I have seen both chickens lay the soft eggs and it started at the same time for both. I added oyster shell today and I hope that helps. They are otherwise behaving normally and eating and drinking well. Is there anything else I should be doing for them?