Hi! I'm sorry that I didn't clarify the point. There's two problem 1. The Airplane mode didn't change. (The state only changes when I turn off kindle.) It just turned on every time. 2. If I go to store in Amazon market, it shows the message "It looks like your kindle is in Airplane Mode and unable to connect to WI-FI." So, I clicked the button to turn Airplane Mode off, airplane mode is still turned on Kindle device. Although I clicked the button "yes", It showed message continuously. (tried almost 10 times) (And it is weird that Airplane Mode didn't show to status bar, but when using Internet, it said that it's on Airplane mode and never connected to WIFI.)
OK, how did you set it up and download books? You need wifi for that, so presumably it was working. I'm tempted to suggest doing a factory reset and starting over since it is brand new and you likely don't have a lot on it yet.
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