Hi Sencer Öznam,
It sounds like your son may have entered a verification code on an untrusted website, which could have allowed someone else to gain access to the Microsoft account linked to his Xbox profile. Since the original sign-in address is no longer being recognized, please start with Microsoft’s official hacked account recovery process.
Enter the email address or phone number that was originally associated with the account. If it still says that the account does not exist, try the Microsoft account sign-in helper, which may provide the appropriate recovery option or a way to contact an account support agent.
In the meantime, please change the password for the email account used as the recovery address, as well as for any other account that used the same or a similar password. Your son should also avoid entering verification codes on Minecraft server websites or sharing them with anyone.
Please note that this is a user-to-user support forum, so contributors cannot access the account or restore its sign-in information directly. Account ownership and recovery can only be reviewed through Microsoft’s official recovery tools. Thank you so much for your understanding.
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