Is there a way of preventing duplicate XML nodes when converting Json to XML?

I am using JsonConvert to deserialise a Json object to XML but because the Json has a different structure for elements at the same level I am getting duplicate nodes in my resulting XML.

My Json looks like this:

{
    "shipments": [
        {
            "id": "A000001",
            "name": "20141208 140652",
            "type": "OUTLET",
            "date": "2014-12-08 14:06:52",
            "status": "SENT",
            "received_at": null,
            "created_at": "2014-12-08 14:06:52",
            "updated_at": null,
            "outlet_id": "SH000064",
        },
        {
            "id": "A000002",
            "name": "20141204 122650",
            "type": "SUPPLIER",
            "date": "2014-12-04 12:26:50",
            "outlet_id": "SH000064",
            "supplier_id": null,
            "status": "RECEIVED",
            "received_at": "2014-12-04 12:28:43",
            "created_at": "2014-12-04 12:26:50",
            "updated_at": "2014-12-04 12:28:43",
        },
    ]
}

After conversion the XML looks like this:

<root>
  <shipments>
    <id>A000001</id>
    <name>20141208 140652</name>
    <type>OUTLET</type>
    <date>2014-12-08 14:06:52</date>
    <status>SENT</status>
    <received_at />
    <created_at>2014-12-08 14:06:52</created_at>
    <updated_at />
    <outlet_id>SH000064</outlet_id>
  </shipments>
  <shipments>
    <id>A000002</id>
    <name>20141204 122650</name>
    <type>SUPPLIER</type>
    <date>2014-12-04 12:26:50</date>
    <outlet_id>SH000064</outlet_id>
    <supplier_id />
    <status>RECEIVED</status>
    <received_at>2014-12-04 12:28:43</received_at>
    <created_at>2014-12-04 12:26:50</created_at>
    <updated_at>2014-12-04 12:28:43</updated_at>
    <outlet_id>SH000064</outlet_id>
  </shipments>
</root>

The code I'm using to convert the Json is:

var document = JsonConvert.DeserializeXmlNode(json, "root");
var xml = document.OuterXml;

The problem is the duplication of the outlet_id node in the second shipments element. The input Json passes validation so I assume this is a common problem. Is there a way around it?