Hii guys, I m peter and I bought a new Kindle paperwhite 7 generation. From a person who sell the device on Internet. It came sealed and brand new and I registered the device with my Amazon account. It was appeared on my devices; I downloaded a book from Kindle store. After a few minutes I couldn't see my Kindle on my account between my devices. So I unregistered it then I tried to registering back on the same account as before. It does not working. Neither with any other account have I tried. So can anybody help me with this? Or Should I contact to Kindle Customer Service Number 0-800-098-8929.