visit account.live.com . click on cant access account. walk through password recovery form. after logging in make sure there is an alternate email and a phone number. Make sure your xbox is off while navigating the website.
If you still need help xbox support will be more than willing to help you through the website
18004639269 or support.xbox.com/.../contact-us to request a call
Microsoft is doing a security check to make sure your account is secure is all.