curl --request PATCH \
  --url https://api.cf.ovrsea.com/v1/purchaseOrders \
  --header 'Content-Type: application/json' \
  --data '
{
  "product_lines": [
    {
      "ordered_quantity": 24,
      "product": {
        "sku": "REF0123458",
        "hs_code": "96032930",
        "description": "blue shirt with a T shape",
        "is_hazardous": "false",
        "hazardous_description": "UN1993",
        "custom_parameters": [
          {
            "name": "parameter1",
            "value": "value1"
          }
        ]
      },
      "reference": "Delivery #1",
      "unit_price": {
        "amount": 150357.99,
        "currency": "USD"
      },
      "volume": 15,
      "volume_unit": "m3"
    }
  ],
  "reference": "PO5792303"
}
'

{
  "reference": "<string>"
}