Update an order

{
  "address": "12 Example Street",
  "city": "London",
  "comments": "",
  "company": "Example Productions Ltd",
  "country": "United Kingdom",
  "created_at": "2026-01-15T09:00:00Z",
  "currency": "GBP",
  "discount": 0,
  "discount_code": "",
  "e_invoice_status": "none",
  "invoice_number": "INV-001234",
  "ip_address": "203.0.113.42",
  "items": "<ul><li>Standard entry &times; 1 &mdash; &pound;50.00</li></ul>",
  "items_array": [
    {
      "amount": "£50.00",
      "description": "Standard entry",
      "discount": "£0.00",
      "entry": {
        "slug": "AbCdEfGh",
        "link": "https://api.au.cr4ce.com/entry/AbCdEfGh",
        "title": "Sustainable Cities Initiative"
      },
      "item_type": "entry",
      "name": "Standard entry",
      "price": {
        "slug": "IjKlMnOp",
        "link": "https://api.au.cr4ce.com/price/IjKlMnOp",
        "title": {
          "en_GB": "Standard entry"
        }
      },
      "quantity": 1
    }
  ],
  "member_number": "",
  "payment_method": "card",
  "payment_status": "paid",
  "postcode": "EC1A 1BB",
  "processing_fee": 1.5,
  "processing_fee_rate": 3,
  "region": "",
  "season": {
    "slug": "QrStUvWx",
    "link": "https://api.au.cr4ce.com/season/QrStUvWx",
    "name": {
      "en_GB": "2025"
    }
  },
  "slug": "YzAbCdEf",
  "state": "",
  "subtotal": 50,
  "tax": 10,
  "tax_rate": 20,
  "tax_rate_details": {
    "country": "GB",
    "link": "https://api.au.cr4ce.com/tax/GhIjKlMn",
    "name": "VAT",
    "rate": 20,
    "region": null,
    "slug": "GhIjKlMn",
    "term": "VAT"
  },
  "tax_term": "VAT",
  "total": 61.5,
  "transaction_date": "2026-01-15T09:01:00Z",
  "transaction_provider": "stripe",
  "transaction_reference": "REDACTED",
  "transaction_status": "succeeded",
  "user": {
    "slug": "OpQrStUv",
    "link": "https://api.au.cr4ce.com/user/OpQrStUv",
    "name": "Jane Smith",
    "first_name": "Jane",
    "last_name": "Smith",
    "email": "jane.smith@example.com"
  },
  "vat_number": "GB123456789"
}