Please help

Hi there, I really need help with a problem that has happened recently. I have been playing fc27 a lot for the past week and have saved up a lot of coins. This morning my son has gone onto my Xbox without my consent and gone onto my ultimate team, he has then proceeded to quick sell a lot of the players in my club and then spent all of the coins in my club on packs. He spent around 400k on 7.5k packs and I need help. I would never ever spend coins on packs as it is a total waste if I wanted to open packs I would just use fc points. Please help because I have spent so much time on this game already and could not have helped what happened as I tell him not to go on my Xbox. Thank you