It can take 24-48 hours for the sync to happen.
Or you can manually force it this way:
Go to Settings > Accounts > Your info
Click on Sign in with local user instead. follow the steps and finish the rest.
(If you don't see the "sign in with a local account instead option, click on "Stop signing into Microsoft apps automatically" first, then relaunch this page. )
Restart the computer (Do Not skip)
Go to Settings > Accounts > Your info
Click on Sign in with Microsoft account instead. follow the steps and finish the rest. Use the new alias this time to sign in.
Restart the computer (Do Not skip)