The crop looks full. Is it hard or soft and puffy? Can you feel of it first thing in the morning before the chicken has eaten or dripunk anything? It should be mostly empty then. Get back to us about if it is full again in the morning. What do you feed? Do you provide granite grit for your chickens to take as they need it? Is she drinking a lot of water? Does she move her head or neck around like she is adjusting her crop?