curl --request POST \
  --url https://api.contazen.ro/v1/supplier-bills/{id}/mark-unpaid \
  --header 'Authorization: Bearer <token>'

{
  "success": true,
  "data": {
    "supplier_bill": {
      "id": "<string>",
      "object": "supplier_bill",
      "invoice_number": "<string>",
      "issue_date": "2023-12-25",
      "due_date": "2023-12-25",
      "currency": "RON",
      "amounts": {
        "tax_exclusive": 123,
        "tax": 123,
        "tax_inclusive": 123,
        "paid": 123,
        "unpaid": 123
      },
      "payment_date": "2023-12-25",
      "payment_amount": 123,
      "supplier": {
        "id": "<string>",
        "name": "<string>",
        "vat_id": "<string>",
        "reg_com": "<string>",
        "address": "<string>",
        "email": "<string>",
        "phone": "<string>"
      },
      "supplier_id": "<string>",
      "expense_id": "<string>",
      "client_id": "<string>",
      "efactura_message_id": 123,
      "efactura_pdf_url": "<string>",
      "order_reference": "<string>",
      "note": "<string>",
      "created_at": 123,
      "updated_at": 123,
      "expense": {},
      "client": {},
      "efactura_message": {
        "id": 123,
        "message_id": "<string>",
        "cif": "<string>",
        "type": "<string>",
        "creation_date": "2023-11-07T05:31:56Z"
      },
      "lines": [
        {}
      ]
    },
    "message": "<string>"
  },
  "meta": {
    "version": "v1",
    "request_id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
    "response_time": "23.45ms"
  }
}