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Looks like the login error is coming from an authentication issue rather than something wrong with your account itself.
It usually happens when the browser session, network, or security token gets out of sync.
The quickest way to fix it is to clear the login session and start fresh.
Try opening the login page in an incognito window or a different browser, make sure your computer’s date and time are set correctly, and temporarily turn off VPN or any ad-block extensions.
If that doesn’t work, switch to another network like mobile data to rule out connection blocks.
Just to confirm, are you signing in to a personal Microsoft account or a work/school account, and does the error happen on all browsers or just one?
Regards,
Aron