curl --request POST \
  --url https://api.zenskar.com/invoices/generate_invoice \
  --header 'Content-Type: application/json' \
  --header 'organisation: <api-key>' \
  --header 'x-api-key: <api-key>' \
  --data '
{
  "customer_id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "contract_id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "from_date": "2023-11-07T05:31:56Z",
  "to_date": "2023-11-07T05:31:56Z",
  "check_duplicate_invoice": true,
  "bill_for_date": "2023-11-07T05:31:56Z",
  "billing_cycle_start_day": 123
}
'

{
  "detail": [
    {
      "loc": [
        "<string>"
      ],
      "msg": "<string>",
      "type": "<string>"
    }
  ]
}