Hi there! Sorry to hear about what happened on your account. Just to confirm, were you able to fully recover your account from this hacker who hacked it? Most of the time, a hacker might change information on your account such as the email address so any licenses like game license and achievements tied to it might disappear.
A 30-day recovery period restores account access, but it doesn’t necessarily mean everything changed by the previous attacker has been corrected.
I would suggest to check your Microsoft account’s recent sign-in activity by going to the https://account.microsoft.com/security page, remove any unfamiliar devices or security information, and make sure the Minecraft Launcher is signed in with the same Microsoft account that originally purchased Java Edition.
It would also help to run through the Microsoft support page for hacked account guide to make sure you have fully recovered your account: https://support.microsoft.com/en-us/accounts-billing/manage/how-to-recover-a-hacked-or-compromised-microsoft-account