about steam coupon

anyone know what is the coupon that given today? I say something in my inventory that about 60-66% coupon and I dunno the discount is for what game. I see something it related to door kicker owner that why I get this coupon but when I click that coupon, steam not display out then later I check my inventory, I no longer see this coupon anymore.
What is that coupon? There is no way to delete coupon right? It only expire by itself when the time come. how can this one suddenly disappear?