Yes i had that quite a few times, especially for business cards, not sure if those are just careless people who entered their details wrongly and have to cancel and redo. Anyone knows if customers have to physically return the products to get refund? In the end , though, they always ended up buying the product. For some people i can see that they cancel the first purchase at usual price and bought the later one with a discount, or a referral. In general i dont really care much, it's Zazzle who loses when this happens, not me.