When your user account is hacked, the #1 thing that you must do before anything else is to protect your identity.
On the internet, no one can distinguish between you and your attacker, and there is nothing that Microsoft or anyone else can do about it.
Think of all the information that may be stored in your stolen account ... email addresses, payment information, details about your life ... your attacker copied all that in an instant and is able to (mis)use it right now.
While you are submitting account recovery forms and dealing with AI bots and waiting for callbacks, your attacker could be sending millions of pieces of spam in your name, threatening your contacts, making purchases with your payment information, obtaining credit in your name, and otherwise impersonating you on the internet. Even if you were to somehow recover your account, which is not likely, it could be filled with malware.
You must disassociate yourself from that account as much as possible. Abandon it and warn everyone you know. Start over with a new account. Always protect your identity.
User accounts get hacked every day. The people who do these things are professionals and they are backed up by an industry of professionals. There is also an industry of professionals (including Microsoft) who are working hard to thwart the attackers. It's a never-ending battle. All of us need to be proactive about our security and privacy on the internet. Protect your identity first.