Hello itay4,
Thank you for reaching out to Microsoft Support!
For Revoke User Session, when you use a non-administrator account, you can only Revoke sign-in session through the POST /me/revokeSignInSessions
endpoint, according to the documentation.
However, for other users, as Andy David - MVP said, you need the administrator role for security reasons, through the POST /users/{id | userPrincipalName}/revokeSignInSessions
endpoint revoked sign-in session.
The official documents may not clearly express this, we are very sorry for the trouble caused to you.
Hope this helps.
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