Security Score help!

Why am I getting an F Security Score? Yesterday I was scoring an A - I don’t think I’ve made any changes to affect this score. I’m a total newbie and am hoping for a very simple solution to fix this. I’ve got Cloudflare with Siteground and WP Rocket. Thanks

The security score was just added yesterday. Odds are what you saw an A for was the “First Byte Time” which used to be the first grade. If you click on the security score it will take you to a page with all of the details (vulnerabilities and headers).