Hi, I hope I can help you with this question.
Currently, unfortunately, it is not possible to use email as an authentication method.
To remove the SMS method, try the following:
Go to Azure Active Directory > Security > Multifactor Authentication > Additional Cloud-based Multifactor Authentication Settings to view the settings.
Under the verification options you can choose which MFA methods are available for all users
These settings are client-wide. If you want to change the MFA method for specific users, In AzureAD, select the specific user. Under Authentication methods, you can specify which methods are available to the user.
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