Hello,
Sorry to say this but your mentioned concern is specifically related to third party Plugins and according to the Envato Policy we don’t provide Support for the third party Plugin issues. You will need to contact the respective Plugin Support in this regard. They will guide you better.
Further, we came across with this WooCommerce guide regarding how you can make use of the Smart Coupons to sell Gift card of any amount, you can check that:
https://woocommerce.com/document/smart-coupons/how-to-sell-gift-card-of-any-amount/
Hopefully, this might help you out in this !
Best Regards