OTP Validation Required against Gift Voucher Redemption. It may be optional or policy based
As the name suggests, Gift Voucher's are mainly used for gifting purpose. Because of which person to whom GV was issued is usually different from the one redeeming it. The buyer of the gift voucher can be X person and the Y person can come and redeem the same. Hence OTP validation is not possible for the same.
We're marking this as unlikely to implement. We appreciate your idea; keep posting.