Using Classic Outlook on Windows for personal email, calendar, and contact management
Microsoft doesn't keep backups of people's mailboxes. If the messages were deleted by the hacker and then purged from the mailbox, they're gone for good. However, since this forum is dedicated to using classic Outlook for Windows, perhaps you were not using a Microsoft mailbox. In that case, you'll need to contain your mail provider. With classic Outlook for Windows, you could make periodic backups of your mail so you don't lose important messages.