Log in to FC Mobile with a junior account

Hello,

My son has a junior EA account used to log in to FC Mobile.

He logged out somehow and to log in back he require to add a code sent to an email like this e****r@anonymous.ea.com Nobody has access to those emails, the codes are not forwarded to my (parent) email address. The account is connected to XBox but it looks like the Xbox is connected to another EA account as well. If he logs in with Xbox the other account is used.

Please help to recover his account. Three support agents were not able to help.