Content restrictions won’t stay on for kids devices using screen time.

My kids have separate ios accounts and I use screen time to monitor and limit usage. It is properly set up. I want content restrictions to be turned on for my kids but at times it turns off on its own. When I try and turn ‘content restrictions’ back on for my children. It toggles green/on but then shuts off after 3 seconds. Why would it not allow me to turn on content restrictions through screen time for my children? Any advice?

thank you