Transaction

{
  "create_auction": {
    "collection": "cosmos1nwacjupxjpgttnscqfvwrj6gs7g2l73kjhq9n963hkr0nux6vg3she79d2",
    "token_id": "820",
    "reserve_price": {
      "amount": "1900000",
      "denom": "uatom"
    },
    "buy_now_price": null,
    "duration": 43200
  }
}