The following steps are for the Outlook iPhone app. If you don't already have it installed on your iPhone, you may download it from the App Store.
Open the Outlook app on your iPhone.
If this is your first time opening the app, follow the steps on the screen to login to your @usssa.com and disregard the remaining steps in this guide.
If you have been using the app for another account, tap the Outlook logo on the top-left of your screen.
Tap the Settings gear on the bottom-left of your screen.
Select Accounts
Tap Email Account.
Enter your @usssa.com email address. You will then be prompted for your password and your multi-factor authentication code.