Unable to Add User to Org with User API

Unable to Add User to Org with User API

I need to automate the creation of email accounts in Zoho and have been using the documentation at https://www.zoho.com/mail/help/api/post-add-user-to-org.html to build my request. I'm using Postman to test and have successfully created an auth token, used it to get my OrgId, and look up my account info. 

When I execute a POST to http://mail.zoho.com/api/organization/<OrgId>/accounts as the documentation shows, the response contains my account information and the user account is not created.

Request:
{
    "role": "member",
    "primaryEmailAddress": "< name@org.com>",
    "timeZone": "US/Eastern",
    "language": "En",
    "displayName": "Name",
    "password": "WTF",
    "userExist": false,
    "country": "us"
}

Response:
"status": {
        "code": 200,
        "description": "success"
    },
[My account info follows]


I've noticed there is another document https://www.zoho.com/mail/help/api/users-api.html that shows the URL to use as http://mail.zoho.com/ap/organization/<OrgId>/accounts/<accountid>. 

Which Url is correct? If I need to supply an accountid how do I obtain/generate it? How do I fix this so I can create a new account?