Account settings

There is no way to change the birthdate on an Xbox account once it is created.

You can learn about privacy and content controls on his account
HERE.

if you are of age and the date of birth for the account was set correctly its possible your account was not graduated correctly. contact support and once verified into your account they will be able to see if the account was graduated. side note if your
account originally had a birth date of something like 1/1/2002 and it was later changed to something like 1/1/1990 the child account settings will still be based off of the original date of birth set on the account.

Try to contact support so they could check your account to confirm if yours is indeed an adult account or a child account. They could also check which email is your parental email in case your account is a child account. You just need to sign in that email
to change your privacy settings.

Hi there!

Please verify that the account of the user says that the user is over 13 years old and if it has a parental account, make sure the purchase has been approved by the parent account

Hey Venialline,

The password may be different for your Microsoft account versus the email account. You may want to try

resetting your password and try signing in again.

Keep us posted if you are still experiencing issues!