Users traveling abroad may experience issues trying to log into their Microsoft account if the account is configured to use text message rather than the authenticator app. These instructions show how to change over to using authenticator.
Open a web browser and navigate to https://office.com
Log into office.com then click the circle with your picture or initials that is in the upper right.
Select the view account link
Select update info on the security info tile.
Click the Add sign-in method button.
Choose Authenticator app from the dropdown
From this point on, you can follow the instructions on this page: https://it.purdue.edu/mfa/