My Steam Account Got Hacked, Can't Reach Support

My Steam account was broken into, and I can't get help from the authorities. I tried to reset my password through email, but my contact info had been changed by the hackers, so I can't get in. Whenever I try to log in with my last password, I get an error message and am kicked off the page. I've put years of work and a lot of money into this account, so getting it back is very important to me. I've tried everything, but I haven't been able to solve the problem. I'm going through a lot of stress and worry right now. The name of my account is burak19**. Please, can you help me? I'm looking forward to your help. Thank you.