Hi @SUROJIT GUIN
If you have set up other verification methods besides Authenticator (such as phone verification, SMS verification)-you can usually see a "Sign in with other methods" link on the login screen, please click to verify with other verification methods. Once the verification is successful, go to the "Other security verification" page, turn off Authenticator, and re-enable it later, see Change your two-step verification method and settings.
If you have only Authenticator set as the verification method and you are the only administrator in your tenant, you must call technical support and have them help you unlock your account. View phone support.
Thanks for your understanding and support.
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