curl --request POST \
  --url https://api.upwell.com/api/rest/bulk-bills \
  --header 'Content-Type: application/json' \
  --data '
{
  "inputs": [
    {
      "billLineItems": {},
      "billLineItemsLastUpdatedAt": "2023-11-07T05:31:56Z",
      "carrierId": "<string>",
      "checkOrAchNumber": "<string>",
      "createdAt": "2023-11-07T05:31:56Z",
      "currency": "AED",
      "dueDate": "<string>",
      "id": "<string>",
      "issueDate": "<string>",
      "notes": "<string>",
      "payToAccount": "<string>",
      "proNumber": "<string>",
      "referenceNumber": "<string>",
      "sourceSystem": "<string>",
      "sourceSystemId": "<string>",
      "sourceSystemMeta": "<unknown>",
      "status": "<string>",
      "tenantId": "<string>",
      "terms": "<string>",
      "totalAmount": 123,
      "updatedAt": "2023-11-07T05:31:56Z",
      "vendor": {},
      "vendorId": "<string>"
    }
  ]
}
'

{
  "createBills": {
    "returning": [
      {
        "billLineItems": [
          {
            "createdAt": "2023-11-07T05:31:56Z",
            "description": "<string>",
            "id": "<string>",
            "item": "<string>",
            "lineNumber": "<string>",
            "quantity": 123,
            "sourceSystem": "<string>",
            "sourceSystemId": "<string>",
            "totalAmount": 123,
            "unitPrice": 123,
            "updatedAt": "2023-11-07T05:31:56Z"
          }
        ],
        "carrierId": "<string>",
        "checkOrAchNumber": "<string>",
        "createdAt": "2023-11-07T05:31:56Z",
        "currency": "AED",
        "dueDate": "<string>",
        "id": "<string>",
        "issueDate": "<string>",
        "notes": "<string>",
        "payToAccount": "<string>",
        "proNumber": "<string>",
        "referenceNumber": "<string>",
        "sourceSystem": "<string>",
        "sourceSystemId": "<string>",
        "sourceSystemMeta": "<unknown>",
        "status": "<string>",
        "terms": "<string>",
        "totalAmount": 123,
        "updatedAt": "2023-11-07T05:31:56Z",
        "vendor": {
          "createdAt": "2023-11-07T05:31:56Z",
          "id": "<string>",
          "name": "<string>",
          "sourceSystem": "<string>",
          "sourceSystemId": "<string>",
          "sourceSystemMeta": "<unknown>",
          "updatedAt": "2023-11-07T05:31:56Z"
        },
        "vendorId": "<string>"
      }
    ]
  }
}