@Naresh Saini, Thanks for posting in Q&A. Based as I know the 2 digital code, is used to do authentication in Microsoft Authenticator app. If the work account is configured in the old device's Microsoft Authenticator app and it is reset. You can go to the following page which set sign in method to remove the previous authenticator method and re-add it to configure authenticator on the new device.
https://mysignins.microsoft.com/security-info
Hope the above information can help.
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