Thank you for your reply.
This issue can be caused by account created in another country, not just wifi connection problem. Just be sure, that if your account is created in another country (USA, Canada, UK etc.) you will not be able to access Kindle store. Your account information should be changed - your address and country should be changed.
To change address and country use procedure below:
1. Go to webpage below - click here
2. Log in using your Amazon account
3. Under "Settings" section, select "Country settings"
4. Click on "Change" and change your country (or address if needed).
5. When done click "Update"
Also, your will be able to access only Italian Kindle store, not your country located store. For example: www.amazon.it is Amazon official website in Italy (note that many books are on Italian language).
Please don't hesitate to ask if you need more information. I'll be happy to help with any follow up questions.
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