This is an accepted solution.
Regarding reactivating a gift card, if you take a look at this doc in our help center - it'll provide you with some additional information. You can disable the gift card that's expired and go ahead and issue a new gift card to your customer from the Product > Gift Card section of your admin. That way your customer will be able to utilize the remaining amount in their previously expired gift card.
If there is anything else I can help you with, please let me know.