Prolapsed cloaca can happen for a number of reasons, and it may happen again. Calcium deficiency, being overweight, and having to wait to lay may be some of the causes. Are you feeding a layer type feed, along with having crushed oyster shell available for free taking? Do you have enough nest boxes for the number of layers you have? What are you doing for treatment? Does the prolapse go back in, or come back out? A lot depends on if any of the tissue has dried out or become necrotic. Can you post any pictures? Here is a good article to read about causes and treatment for prolapses:
https://the-chicken-chick.com/prolapse-vent-causes-treatment-graphic/
Are you feeding a layer type feed, along with having crushed oyster shell available for free taking?
I’d rather not feed layer to my roosters. I feed Nutrena All flock with limited treats. Always have Oyster shell available. And my birds do eat it. I’ve seen these particular pullets eat it as well.
Do you have enough nest boxes for the number of layers you have?
Hmmmm... never thought about this. I have about 27 hens/pullets and 5 nest boxes but the majority of them prefer to lay in only 2. I’ve tried to encourage them to lay in the other 3 but they are chickens... and stubborn.
What are you doing for treatment?
I was following other advice and cold hosed/cleaned her up and put honey on her vent. I gently pushed everything back in and put a diaper on with a rolled up rag on her vent for some pressure to keep it in. Took it off after a couple hours and they keep it in for a time. Longest it stayed in was 2 days. Then they laid eggs and this is the 3rd time I’ve tried to help them and keep their prolapse in.
Does the prolapse go back in, or come back out?
See above. It won’t go in on its own. And comes back out with or without laying an egg.
A lot depends on if any of the tissue has dried out or become necrotic. Can you post any pictures?
I will try and get photos later. It isn’t narcotic, the worst one had some dried scabs and after I cold hosed her vent I was able to get them off. It’s definitely an angry red color. In the article you sent mentioned hydrocortisone cream, might try that today. There seems to be a million different ways to treat this. Each article I read says something different.