Cannot Recover Hijacked Hotmail Account

Hi,

Attempting to modify my Xbox Live Membership prompted me to sign in to the Hotmail account I have tied to Xbox Live. I've found my Hotmail password no longer works, and when attempting to reset the password via the methods available, I also found that that the answer to my Security Question has also been changed, and any existing alternative emails have been deleted, leaving me unable to sign in or reset the password to that account. 

The Hotmail account was created nearly a decade ago and it has been years since I've sent or received any emails from it (I use the account for Xbox Live and nothing more). Because of this, the information I could provide to the Security Questionnaire was limited to my Xbox Live payment details and the password I used to use before it was changed by the hijacker. This information was held to be not sufficient enough to recover my account. 

I would very much like my account back, however after my application via the Questionnaire was rejected, I'm not sure how to proceed. 

Any advice on how the account could still be recovered? I'm still signed in to my Hotmail via Xbox Live, if that helps at all. 

Thanks :)