If browser sign-in works but Windows doesn't, go to Settings > Accounts > Email & accounts (or Access work or school), remove the problematic account, restart, and re-add it. This clears a corrupted local credential cache, which is a common cause after Windows updates.
Go to account.live.com/password/reset from another device (phone or another computer). If you can get in there, the account itself is fine and the issue is local to the Surface Pro.