How to disable multiple gifcards from being used on Magento?

I recently had a gift card sale on a daily deal site where shoppers could buy a gift card to my shop at a discount price. Terms was 2 vouchers per account and they cannot be used in the same order.

I could not find an option on Magento’s back end to disable multiple gift cards from being used in the same order, and have been getting a lot of orders where ppl are using both giftcards.

Is there anyway for me to do this? Thank you in advance!