@Lam Vinh Khang
Thank you for your post!
Unfortunately, the User Administrator role does not have permissions to manage MFA. For more info - User Administrator Built-in role
If you'd like to manage MFA within your tenant, you can leverage the following roles:
Authentication Administrator - Users with this role can set or reset any authentication method (including passwords) for non-administrators and some roles.
Privileged Authentication Administrator - Users with this role can set or reset any authentication method (including passwords) for any user, including Global Administrators.
Authentication Policy Administrator - Users with this role can configure the authentication methods policy, tenant-wide MFA settings, and password protection policy.
If you have any other questions, please let me know.
Thank you for your time and patience throughout this issue.
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