post
https://acquirersandbox.rp-2023app.com/openapi/v2/refund/detail
Retrieve refund transaction details by either the acquirer-assigned refund
ID (refundSn) or the merchant's refund reference (merchantRefundSn).
Response includes refund status, refunded amount, currency, timestamps
and related settlement metadata.
When inherited from the original payment, response also includes optional subMerchantCode.
