Any way to get Microsoft Username when you didn't know it and account got hacked?

Welcome Ivory,

I’m sorry you’re dealing with this. Since the email address and password were changed, the first priority is to identify the Microsoft account username or another sign-in alias before attempting account recovery.

Please try these steps:

1, Try Microsoft’s username lookup

• Go to Microsoft’s official Forgotten username guidance: Forgotten your Microsoft account username
• If you previously added a recovery phone number or alternate email address, Microsoft can send a security code there. After verification, Microsoft may display a hint for the username associated with that security information.

2, Try other sign-in information you previously associated with the account

• If you remember an old email address, phone number, or Skype name connected to the account, try that information when starting account recovery. This can be useful even if the account’s sign-in information appears to have stopped working.
• Search any old email accounts for messages from Microsoft, Mojang, or Minecraft. Purchase receipts, account notifications, or security emails may contain the original account information.
• Check whether you still have Minecraft installed on another device where you were previously signed in. The username, gamertag, or account details may still be visible in the Minecraft Launcher.
• Look for any saved purchase receipts, order numbers, or payment records related to the Minecraft purchase.
• If you remember your in-game Minecraft name (gamertag), that may also help identify the account.

Looking forward to your update.