POST "https://api.rewards.wlloyalty.net/events"
Content-Type: "application/json"
X-Api-Key: foobar123
Authorization: Bearer ...

{
  "type": "INVOICE_PAID",
  "subject": "431a81d8-3936-4ccc-8955-2009c078e6c8",
  "payload": {
    "invoiceId": "031a81d8-2936-4ccc-8955-3009c078e6f1",
    "balance": 0,
    "overdue": true,
    "daysLate": 4,
    "paymentMethod": "CASH"
  }
}