BillingInfo

{
    "id": "FID001",
    "type": "BillingInfo",
    "attributes": {
        "state": "ok",
        "oldestUnpaidInvoiceDueDate": "2019-08-24T14:15:22Z"
    },
    "relationships": {
        "invoices": {
            "data": [
                {
                    "id": "FID001",
                    "type": "Invoice"
                }
            ]
        }
    }
}