Siebel REST API - createAccount returns HTTP 500 on sucess

Greetings,

I'm using SIEBEL IP16 REST API to create accounts. The account is created sucessfully. I'm getting a json with the account ID. However the HTTP status code of the request is 500 - Internal error.

Anyone knows how to fix this?

Below the request/response info:

Thank u.

Regards,

Daniel

Request

POST http://X.X.X.X:9001/siebel-rest/v1.0/service/Account/CreateAccount/

POST data:

{

  "body":{

        "Account IO":{

           "MessageType":"Integration Object",

           "IntObjectName":"Account IO",

           "ListOfAccount IO":{

           "Account":{"Name": "Shannon Jefferson"}

           }

        }

    }

}

Response

data:

{"Account Id":"1-UH6A"}

Response code: 500

Response message: Internal Server Error