Hello @Anonymous ,
Thanks for reaching out and apologies for the delayed response.
Members of the 'AAD DC Administrators' group should ideally be able to get access and administer the complete Azure AD managed domain services. However, if you're having an issue with a certain user account, could you kindly create a new user and add them to the 'AAD DC Administrators' group to observe their behavior? Additionally, it's good to reset non-working users' passwords to verify behavior since, for example, if Azure AD DS does not contain the user's password hashes due to some reason as explained here, then you may have issues with AAD DS.
Hope this helps.
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