No sweat! You can temporarily freeze your card anytime in the STACK app > Cards > Choose which card you want to freeze, and tap on Freeze Card. The image of your card should look frozen over once done!
If you think your card is permanently lost or stolen, freeze it in the app and then give us a call at 1-877-STACK-01 so we can help you out.
If you don't have access to your app, give us a shout and we'll be happy to freeze it for you.