If you are redeeming a gift code and receive the error message "There was an error processing your request. Please try again later," or "Invalid gift code," you may be trying to add a gift code to an account that is already active with a gift or promotional subscription.
A gift code cannot be added to an existing promo or gift subscription. Please wait until the end of your current gift or promotional period. Once your subscription is inactive, you can return to the gift redemption process at historyvault.com/redeem/gift to redeem your new gift code and restart your subscription.