Device Compromised" notice in iPhone Settings

I got a “Device Compromised” notice in my Settings in red, with no explanation and no instructions on what to do or even how to clear the notice.

There was no e-mail from Apple and when I went to check my account, there was nothing out of order. Only my devices were listed, there were no payments that hadn't been made by me, no one had logged into my account without the 2-factor authentication.

I have gotten random phishing e-mails before saying my account has been hacked, but these were clearly spam, and I reported them to Apple. They don't tell you what they do with them from there. This notice was right on my iPhone in the Settings, not from some outside e-mail or text.

When I look this up, all it says is to change your account password, which I did, but why did I get this notice and how do I find out what it means?

Has anyone had this happen before?

Thank you.