iCloud issues after downgrading from iOS 27 public beta

About two weeks ago, I wanted to try the beta. I decided to downgrade back to the latest signed iOS 26. Ever since using the Apple Devices tool to do the restore, I am unable to log into iCloud from any device and my photos/notes/messages stored in iCloud don’t sync to my phone. The login issue is I seem to get a login loop in iCloud.com. I successfully log in, then within two seconds immediately kicked back out to the login screen. Apple techs have been working with me for over a week and still have not identified or fixed the issue yet. Has anyone else experienced this?