My account got hacked and i cant do anything about it. Please help

I am VERY mad because my Microsoft account that is about 8 years old and I don't remember all the details about it. It got hacked the other day since then I've been trying everything to get it back. the guy that hacked my account before I even could do anything he changed the email address of the account password and cellphone number. I tried their guide on how to restore your account a couple of times and tried doing anything and I still cannot get it. PLEASE help me get it back this account means a lot to me. this is an old gaming account I have I play a lot of Minecraft on it and this account is very precious to me.

I'm asking this question in a spare account that means nothing to me.

:)