Our client is looking to send a coupon only to shoppers who bought a specific SKU.

To do this, we have AMPscript that checks the SKU and if the SKU is found, the coupon is inserted.

However, what we're finding is that a coupon is always assigned and only displays in emails for those who bought the SKU in question...but we're going to run out of coupon codes if we keep doing it this way.

We tried to nest the AMPscript, but it appears the script is always executed, regardless of whether or not it's displayed.

How do we make it so a coupon is assigned only if the SKU is in the list of purchased products??!?!