This endpoint handles traditional proposal reserved credit change rollback (implemented by vendor)
Will keep retrying until successful. Implementer must handle properly to avoid duplicate credits
Platform product ID
Verification code, md5(platform_id + uuid + account + canceled_id + transaction_id + platform_secret)
Platform-defined unique request serial number
Player account
Type: 1. Buy-in 2. Add-on
Transaction serial number to cancel, must be unique and non-empty
Transaction serial number, must be unique and non-empty (1-128 characters, ASCII 32-126 printable characters only, ` and ~ are prohibited)
Amount, must be positive integer
Player proposal ID, cannot be empty