Meijer Mperks Help

So Meijer has a 20% off one general merchandise item offer going on right now, so I signed up for an account to use it on Kindle cards like I've seen mentioned before. When I went to the self-checkout, I logged into my Mperks account, and scanned the Kindle card, but saw no discount taken off.

This happen for anyone else? Did I not do it right? Or are they now excluding Kindle cards?