Applying a Gift Card on the consumer side can sometimes be confusing for customers. It is worth noting, this is high on our priority list to improve and an area we are aware of.
At this point, the way Gift Cards work on the consumer side is that the customer applies the entire Gift Card to their file as credits.
To do this, the Customer simply goes to their Account Dropdown and chooses Credits & Gift Cards. From there, they choose Redeem Gift Card, type in the code, and the credits will be added to their account.
Where there is confusion, is that the Customer will sometimes try to use the promo code box to redeem a card or expect to see a Gift Card box somewhere during the purchase process.