curl --request GET \
  --url https://openapi.pluuug.com/v1/settlement \
  --header 'X-API-Key: <api-key>' \
  --header 'X-Signature: <api-key>'

{
  "results": [
    {
      "id": 123,
      "title": "<string>",
      "amount": 1,
      "additionalAmount": 1,
      "vat": 1,
      "typeAlias": "<string>",
      "created": "2023-11-07T05:31:56Z",
      "contract": {
        "id": 123,
        "title": "<string>",
        "amount": 123,
        "startDate": "2023-12-25",
        "endDate": "2023-12-25"
      },
      "dueDate": "2023-12-25",
      "settledDate": "2023-12-25"
    }
  ],
  "next": "http://api.example.org/accounts/?cursor=cD00ODY%3D\"",
  "previous": "http://api.example.org/accounts/?cursor=cj0xJnA9NDg3"
}