API에서 taxFreeAmount 값이 전송되지 않습니다.

my request log
{
    "paymentKey": "tnhig20251121102047bvrO8",
    "orderId": "39_C_1_51_1763688046",
    "amount": "9026",
    "taxFreeAmount": 4026
}

toss request log
{
  "paymentKey": "tnhig20251121102047bvrO8",
  "orderId": "39_C_1_51_1763688046",
  "amount": 9026
}

request log
{
  "mId": "tnhigogz5bi",
  "lastTransactionKey": "txrd_a01kaj00e2mrrpmscg7w050d8g7",
  "paymentKey": "tnhig20251121102047bvrO8",
  "orderId": "39_C_1_51_1763688046",
  "orderName": "안심 33kg(1+|한우거세)",
  "taxExemptionAmount": 0,
  "status": "DONE",
  "requestedAt": "2025-11-21T10:20:47+09:00",
  "approvedAt": "2025-11-21T10:21:09+09:00",
  "useEscrow": false,
  "cultureExpense": false,
  ...
  "receipt": {
    "url": "https://dashboard-sandbox.tosspayments.com/receipt/redirection?transactionId=tnhig20251121102047bvrO8&ref=PX"
  },
  "checkout": {
    "url": "https://api.tosspayments.com/v1/payments/tnhig20251121102047bvrO8/checkout"
  },
  "currency": "KRW",
  "totalAmount": 9026,
  "balanceAmount": 9026,
  "suppliedAmount": 8205,
  "vat": 821,
  "taxFreeAmount": 0,
  "method": "카드",
  "version": "2022-11-16",
  "metadata": null
}