Hi, 杰.
I'm Jen. I'm an independent advisor and would happily help you figure this out.
I also encountered this error when I signed in to a child account in Copilot. Unfortunately, this is a user-to-user forum and we have no access to accounts to confirm if it's an account issue. Have you tried checking if your date of birth is correct in your account? If it is and you are not using a child account, I suggest clearing your browser's cache, cookies, and site data.
If the issue persists even while using other browsers, I suggest reaching out to support for assistance regarding your account.
https://support.microsoft.com/en-us/home/contac...
Feel free to share how it went.
Kind regards.