
Hey there! Nice to meet you!
Since your son no longer has access to his security information, kindly click on the option 'I didn’t get a code' when prompted for a code at sign-in at the 'I don’t have access to these' when he is resetting his password, then follow the instructions. account.microsoft.com
He will be asked to fill out a security questionnaire. He will be asked for info, like the subject lines of an email he recently sent from his account, his birthdate, credit card info, and other details only he would know.
Go to Recover your Microsoft account (https://support.microsoft.com/help/17875) for tips on how to successfully fill out the security questionnaire.
Note: There may be a 30-day waiting period to get full access to the account again.
Thank you for your kindness and understanding! Please let me know if you need anything else.
Best regards,
Darhyl