From your description, it sounds like she has an impacted crop. You can massage her crop in an upwards motion a least three time a day to help break things up. Google this method to help with impacted crop. When you get the grit also get some coconut oil from the grocery store to mix with it. Chickens (at least mine anyway) love it and it’s a good way to get them to eat the grit quickly. One of my Marans recently had an impacted crop from eating to much hay and this was my approach to help her with it. She was fine again within a week.