@Tomomi Kikuchi Thanks for reaching out. Follow these steps to give it a try :
1) Sign in to https://myapps.microsoft.com.
2) Select your account name in the top right, then select profile.
3) Select Additional security verification.
4) From the How would you like to respond? section of the Additional security verification page, update the phone number information for your Authentication phone (your primary mobile device) and your Office phone.
5) Select the box next to the Alternate authentication phone option, and then type in a secondary phone number where you can receive phone calls if you can't access your primary device.
6) Click Save.
You can also follow https://learn.microsoft.com/en-us/azure/active-directory/user-help/multi-factor-authentication-end-user-manage-settings#add-or-change-your-phone-number for more information.
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