Hi @철현 김
Thank you for posting your query on Q&A.
I understand that you have delete the Entra ID tenant/ directory in your azure subscription.
Deleting the default directory in Microsoft Entra ID (AAD) is possible only if it has no resources or subscriptions associated with it, deleting a tenant in Microsoft Entra ID will also delete all resources and users in the tenant, including the owner account. If you have the other tenant and delete the default tenant from your subscription the owner account will not be deleted, it will be removed from the directory and become a guest user in another directory. could you please sign in with the new user ID which is shown on secondary tenant for more information about error AADSTS50020 please refer the below document.
https://learn.microsoft.com/en-us/troubleshoot/azure/active-directory/error-code-aadsts50020-user-account-identity-provider-does-not-exist#cause-8-a-previously-deleted-user-name-was-re-created-by-the-home-tenant-administrator
I hope this answer helps! please Feel free to ask any questions you may have.
Thanks,
Akhilesh.
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