Adding Office 365 Exchange Active Sync Account to Android Native Email, Calendar and Contacts Apps
If you are using two-factor authentication in Office 365 (AKA multi-factor authentication) you MUST use an App Password instead of your Office 365 Login Password when creating your Exchange Active Sync account on an Android device.
See the following link to learn how to create an App Password:
Note - if you try to use the app password when setting up your native email account on your phone when using office 365 multi-factor authentication, and you get an error message that says "user name or password is not correct" then it is very likely you need a new app password for your android email setup. You will need to logon to your office 365 account, go to my account, security privacy, additional security verification, and create a new app password. Enter this app password instead of your usual password when signing in to your email online and it will work!