Problem Inserting Data to Table PersonWantsOrg via REST API

Hi,

We would like to connct 1IM with our request system with REST API, in this case writing data to table PersonWantsOrg is required.

We managed to deal with authentications, now it is able to insert data to PersonWantsOrg by using Object Browser.

While we tried with REST API, we just kept getting response below:

{
    "responseStatus": {
        "message""An error occured."
    },
    "errorString""An error occured.",
    "exceptions": [
        {
            "number"2072000,
            "message""An error occured."
        }
    ]
}
And here is the body we sent:
{
    "values": {
        "UID_Org""14964D15-4DC0-4C06-88ED-75E18C1AC42A",
        "UID_PersonOrdered""bd5e4ba6-c53a-4427-81bd-97736bbcf028"
    }
}
System shows these 2 fields are required, and the GUID's are copied from table Person and ITShopOrg.
The version of 1IM is 7.1.2, 1IM's API web portal is used for testing.
Can anyone help?
Thanks!