Microsoft take security very seriously, and strongly recommend you use 2 Factor Authentication (2FA) to safeguard your account.
It's possible to change how your 2FA works, and you can choose between using the Microsoft Authenticator App (recommended) or receiving an SMS message to your phone.
To update your 2FA settings:
1. Point to your username in the top right hand corner of the Office dashboard and choose View Account.
2. From the account dashboard, choose Security Info (note you'll be asked to approve this page request with your existing approval method).
3. Select the option to change your default sign in method.
4. Choose your preferred method to authenticate your account.
You can also add other security details on this page or change your mobile phone number if required.