Use the same code more than 1 time

Hello,

I found the problem that if someone buy a gift car and he receive the code in a complete email.

But, The can use the code 2, 3 or 4 times, as they want.
The quantity is being less buy always they can buy with some kind of discount.

Could you tell me how Can I fix it?

Thank you!

https://www.ads-software.com/plugins/yith-woocommerce-gift-cards/