Delete attempt as admin: SOAP-ENV:Server.InsufficientPermissionsException

I'm working on a local system.

I can add and edit users... So, POST and PATCH are working. I go to delete the same user I just edited, but am getting:

// DELETE 'http://localhost/InnovatorServer12/server/odata/User('30B991F927274FA3829655F50C99472E')

{
    "error": {
        "code": "SOAP-ENV:Server.InsufficientPermissionsException",
        "message": "You have insufficient permissions to perform 'delete' operation."
    }
}

Why? How to fix this?