Hello
I have had one of my girls with a similar issue last week, for 2 days she stood around eyes closed, not eating, being very dosile and looking very unwell.
She is now fine, back laying had 5 days without an egg.
Turns out she was suffering from heat stress caused by high temperatures. Now know to keep an eye on them more with the heat, spray them with water. lots more shade made for them, water kept in shade etc
Learning all the time but getting there ;D