DUO MFA app push notifications not received on phones out the United States

It has been discovered that DUO app push notification are sometimes not received on phones out the United States.

This might be due to the data plan that is applied to specific phones.

NOTES:

When traveling abroad, Duo push notifications are generally going to be more reliable than calls or texts. As long as the phone has a data connection, push notifications should be possible. However, please see the information below for troubleshooting.
For short-term travel where push notifications are still not working, even after following the troubleshooting steps below, try using the passcode generated in the Duo app on your phone (does not require any data connectivity).
For long-term travel (such as while studying abroad), contact the ITS Service Desk (ServiceDesk@pomona.edu) ideally before travel. We have a variety of options, including the provisioning of Duo tokens (where phone use/availability is limited) and other options.

As an alternative to using the DUO App, it should still be possible to still receive texts and calls to the same phone using the following steps:

Open a new incognito window (Google Chrome) or new private window (Safari, Firefox or Edge).
Visit the desired Pomona College information resources that requires authentication, like http://mail.pomona.edu .
You should be taken to a Microsoft login page (with Stover Walk in the background). Authenticate there with your Pomona College username and password.
When you see the Check for a Duo Push prompt, click 'Other options' instead.
Choose to have DUO call or text the new number. Enter the code that you receive from the call or text.

NOTE: The same data plan problem might cause trouble with texts. Use the call instead if so.

You should now be logged into the desired Pomona College information resources.

NOTE:

If that doesn't work, please report trouble to ServiceDesk@pomona.edu .