Epic games account hacked, how do I get the back?

I'm asking for a friend.

His Epic Games account was hacked and, we suspect, sold. For some time now, jmd from England has been playing on his account. The email has already changed the email and password. The support doesn't help and we wanted to take action against them ourselves (even if he didn't do anything himself, buying and selling Fortnite accounts is prohibited). Can anyone give us some advice would be very happy, especially because he has been playing on the account for a very long time and not a little money has flowed into it.

Do you have the account again?