The difference between login.live.com
and login.microsoft.com
is that the former is for logging in with a personal Microsoft account, and the latter is for logging in with a work/school account. Therefore, if you are trying to log in with a personal account, it will default to the login.live.com URL.
If you want to log in using the login.microsoft.com URL, make sure the user logged in is a work account or a guest account that has joined organization.
Hope this helps.
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