child account cannot log in

My child (under 13) is trying unsuccessfully to launch Star Wars Battlefront II Celebration Edition through Steam on Windows 11. When he does so, the Origin app launches and prompts him to log in. He puts in the correct user credentials, and then gets the message: "We cannot complete this action at this time. If you need assistance, please reference help.ea.com or answers.ea.com."

I know he is putting in the correct username password, because when he tries to log into the same Origin app launched from Windows (as opposed to launched from Steam), he is able to log in successfully to his account (though of course the game doesn't appear in his library because his EA account has not yet been linked with Steam).

The issue has been preventing him from ever successfully launching the game through Steam.

I've already tried uninstalling the Origin app and re-installing it, but it has not resolved the issue.

I've already checked my router parental controls, and the router is not blocking the connection to Origin.

Another of my children, also under 13, has no problem when trying to launch the game from his Steam account on a separate Windows 11 computer. So I don't get why one child is able to log in and another cannot, why one child was able to link his EA child account to Steam, and why the other child is unable to do so.

Any thoughts?