curl --request GET \
  --url https://api.sandbox.tesouro.com/finops/v1/receivables/{receivable_id}/mails/{mail_id} \
  --header 'Authorization: Bearer <token>' \
  --header 'x-finops-version: <x-finops-version>' \
  --header 'x-organization-id: <x-organization-id>'

{
  "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "created_at": "2023-11-07T05:31:56Z",
  "updated_at": "2023-11-07T05:31:56Z",
  "status": "pending",
  "recipients": {
    "bcc": [
      {
        "email": "jsmith@example.com",
        "is_success": true,
        "error": "<string>"
      }
    ],
    "cc": [
      {
        "email": "jsmith@example.com",
        "is_success": true,
        "error": "<string>"
      }
    ],
    "to": [
      {
        "email": "jsmith@example.com",
        "is_success": true,
        "error": "<string>"
      }
    ]
  }
}