Why is JD.COM Omega so cheap?

In fact, it is what is cheap and what is in stock. Just like purchasing in advance, act as a second-hand dealer. But there is no authorization, and it is not a physical store, so it cannot be stamped. In-store warranty only, not global warranty. The watch is real. I bought a constellation. Really cheap 10000 or so. But the warranty card doesn't match the watch number. They admit the discrepancy, but they are responsible for the goods.