Hello @Maksym Dilanian,
Thank you for posting your query on Microsoft Q&A.
Based on your description, I understand that after migrating from legacy authentication methods to modern ones, you were unable to use the TOTP method, as the "Use a verification code" option is missing from the MFA prompt page.
This issue could occur if the "Allow use of Microsoft Authenticator OTP" option is not enabled in your modern authentication method policies. To enable it, please follow these steps:
- Log in to the Azure portal.
- Navigate to Microsoft Entra ID > Security > Authentication methods.
- Under Authentication method policies, click on Microsoft Authenticator Settings.
- Click Configure.
- Ensure that the option "Allow use of Microsoft Authenticator OTP" is enabled.
Please refer to the screenshot below for better understanding.
I hope this information is helpful. Please feel free to reach out if you have any further questions.
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Thanks,
Raja Pothuraju.