On October 3rd, 2018 we activated the MFA feature for Microsoft. This feature creates a more secure environment when associates are using Microsoft products.
Solution: Delete BMC email from your phone. Re-add email using exchange option. Once you get to the MFA registration it will ask you for your code. If you don't get one select resend option and a text will be sent.
You may select the sync calendar option, as default it is off.
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** If your iOS is less than 11 then you will need to download outlook on your device and won't be able to use the native app.