Allow changes to photos not working under Screen Time restrictions on iPhone 15 Pro

I have Screen Time turned on for my kid. Under Content & Privacy Restrictions / Privacy, I've set a restriction on letting apps access her photos. I went in there to switch it to "Allow Changes" so she can let a new app have access to her photos. However, there's a problem. The little check mark switches to "Allow Changes" when I click on it - but it doesn't ask for my Screen Time passcode. And then when I exit back to the main privacy screen, Photos remains at "Don't Allow," and the option to allow access to Photos in the app and through Settings is not available. I've tried allowing changes to Accounts and everything else I can think of, and I still can't get the privacy settings to work properly.

[Re-Titled by Moderator]