Hi @Vamsi Y ,
"Microsoft.Exchange.Data.Storage.TenantAccessBlockedException"
Are you attempting to login in Exchange Online OWA via https://outlook.office.com?
If this is the case, from the error message, please have a try again now and see it can work, as sometimes this error is just temporary and might clear out automatically in a few minutes.
In case the error persists, it's suggested to reach out to your Exchange administrator to help look into it further from the backend. For example, the admin can go to the Microsoft 365 admin portal and make sure your user account is not blocked.
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