When including 3PL items in an order, a campaignId value must be included in the request. This is the id of the store that contains the 3PL products and can be obtained from the URL when on the store admin page. See details here.
For 3PL items, the orderItemGroup is simpler because there is no decoration information needed. designData is omitted and the sku field is provided with a value corresponding to one of the 3PL SKUs registered in the store.
Below is an example of a 3PL orderItemGroup.
{
"declaredValue": 12,
"id": "47b8274d-ae30-4564-a6f8-66bc4504829a",
"sku": "7352583123",
"quantity": 8
}If you have registered values for Vendor SKU on the 3PL items in the store, the Vendor SKU can be used instead on the orderItemGroup.
{
"declaredValue": 12,
"id": "47b8274d-ae30-4564-a6f8-66bc4504829a",
"vendorSKU": "QAR-3431",
"quantity": 8
}