i need help kicking a hacker out of the account

A couple of weeks ago my little sister’s account was hacked, the hacker kicked her out from any devices she was logged in and changed her password, email and add them self as a parent control making us unable to log back in or even change the password. we contacted roblox support multiple times but they were not helpful at all either bots replying or getting no reply at all.

yesterday, my sister somehow managed to get back in and we quickly changed everything back to normal my other sister even added her own account as a parental control. today the hacker got back in and changed every thing including the 2fa and kicked my sister out again, we tried logging with a passkey and it didn’t work, we tried changing the password but because they changed we were unable to that either.

we know the hacker’s username and email (the account for parental control) so i’m wondering if someone could help us somehow, all we need is to get our account back and kick the hacker out for good even their parent control account.

(sorry if any of this is not understandable english is not my first language)