Error Code:

Error Code	51004
Message	The user account {identifier} does not exist in the {tenant} directory. To sign into this application, the account must be added to the directory.
Remediation	An application likely chose the wrong tenant to sign into, and the currently logged in user was prevented from doing so since they did not exist in your tenant. If this user should be able to log in, add them as a guest. See docs here: https://learn.microsoft.com/entra/external-id/add-users-administrator