What to do for a stolen xbox account and threats?

Local authorities and contact your internet service provider. This will most likely be the best option.

There's also a support page for a compromised account you can follow.

https://beta.support.xbox.com/help/account-profile/manage-account/compromised-account-solution

Hi there,

Be sure to reach out to your local police department, if you haven't done so already, about the threats. They can advise you on next steps you can take. You can also reach out to your ISP about the threat to the home internet as that is a crime in most places.

If you haven't done so yet, or have not been able to recover it, be sure to follow the steps

here.

This would also be a good time to update the passwords on all the family accounts, including the login for the home wi-fi, making sure all the passwords are unique and that you have them all listed in a secure password manager.

Sorry this is happening but this individual is not the smartest because he has left a road directly back to him Please contact your authorities. Go to the department and tell them of the threats and exactly what this individual has done. Do not alert the
individual you are aware of them Most likely they will cut and run and you will not hear from them again. You most likely have all types of hacking malware in your system. If you are using a router make sure that is secured?? You possibly could be getting
an individual that has access to more than the xbox. Adjnust your xbox security and possibly get a manual dns for safety. Most Manual DNS servers are more secure than your current home one. https://gearnuke.com/best-gaming-dns-servers-xbox-one-ps4-nintendo-switch/

These are all just helpful hints but first contact your authorities them you can do all the passwords security and dns protocols for your safety.

Report and block them.

Microsoft will check their records for indications of hacking and if they find evidence, they will act on it. As Undeadfire stated, not everyone that says they hacked, actually did. Most people can't hack. Hacking another account to find their password,
usually the account owner reports their stolen account to Microsoft.

Microsoft does not take threats lightly. Depending on what the threat was and how much Microsoft believes the person can do it will determine what Microsoft does. At the very least, Microsoft can get them on threatening another player or what is called,
cyber-bullying/cyber-abuse. Microsoft is good at acting on these things and will insure your Xbox LIVE experience is enjoyable.

Never be afraid to report.