Hello Ratna,
Thank you for contacting Microsoft Community.
As you're unable to sign in and the Microsoft Authenticator app is not displaying the one-time passcode, the recommended action is to contact your organization's IT administrator. They will be able to reset your Multi-Factor Authentication (MFA) registration and assist with reconfiguring access through Microsoft Entra admin center.
Once the reset is completed, you should be able to re-register your account in the Authenticator app and regain access.
You can follow the identical instructions below to request that the administrator reset your authentication method:
1 – Navigate to Microsoft 365 Admin Center, you can click Identity at the sidebar
Microsoft 365 Admin Center website: Microsoft 365 admin center
It will lead you to Microsoft Entra Admin Center (Microsoft Entra - Microsoft Entra admin center)
Select Users
Click All users
Click on to the affected account name (your account)
For example:
2 – Select "Authentication Methods"
3 – Click "Require re-register multifactor authentication"
Next time the user sign in, the system will require them to set up a new authentication method. By using this, the affected user can re-set up the right authentication method
I hope this information is helpful. Feel free to reach out again if the issue persists or if additional support is required.
Best Regards,
Demi-N | Microsoft Community Support Specialist