Determine if the UnionPay Refund transaction you wish to void was assisted or not by looking at the Refund receipt. If UNIONPAY is printed under APPROVED on the receipt, then the transaction was assisted. Proceed as follows:
If the original UnionPay Refund was not assisted, then perform an Void-Refund as you normally would.
If the original UnionPay Refund was assisted, then start an assisted UnionPay transaction for Void-Refund and follow the prompts on screen. If needed, refer to the Void-Refund transaction and to the additional prompts for UnionPay cards.