Hi Piotr Kwasnik,
Thank you for reaching out to us on the Microsoft Q&A forum.
This topic is currently not supported in the Q&A forums.
Remove all accounts from XBOX and format reset XBOX. Then create a Microsoft XBOX account over 18 years old. Then sign in on new updated XBOX.
We recommend initiating a new discussion through the XBOX Community where our moderators are readily available there to assist you and provide guidance.
If you are having difficulty accessing Xbox Support Live Chat, you can also try contacting Xbox support via phone XBOX support
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