Referral Program email broken

[st3v3]

Hi i just tested my referral program for the first time and when a user receives an email this is what it says .   

 

We are pleased to offer you a voucher worth {discount_display} (voucher # {discount_name}) that you can use on your next order. Get referred and earn a discount voucher of 5%! It's very easy to sign up. Just click here!

 

 

as you can see it is broken it displays {discount_display} (voucher # {discount_name}) .  im sure its an easy fix just have no clue where to start.

 

Thank you.

www.arcticforcecomputers.ca