Okay. First off, please make sure that your Kindle is connected to your wireless network, as follows:
From the Home screen, tap the Menu
icon (with three horizontal bars), then tap Settings
> Wi-Fi Networks
Make sure that the Kindle is connected to your wireless network (indicated by a checkmark next to it); if not, tap on your network to connect to it accordingly.
Done that, carry out a soft reset of the Kindle as follows:Press and hold the Power button for a full 20 seconds.
After the first 6 to 8 seconds, the screen will go blank, which is normal. Continue holding the Power button. After the 20 seconds, release the Power button.
Next, check if this resolves your issue with accessing the Kindle Store. If the same issue persists, please power cycle your router as well, as follows:
Disconnect the power supply from the modem/router, wait for 30 seconds, then re-connect the power supply to the modem/router.
Restart the Kindle and check the issue one more time.
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