Email Account Hacked

so my old email account that has important information in emails such as bank details, addresses and my cv inside has been hacked, my secret question has been changed so i dont know the answer and the email to reset password is someone elses email so theres no way i can reset my password, i really need to get back into the email, i tried to submit a form but it said i didnt provide enough infomation, they asked questions such as billing and a xbox live account but i dont even have a xbox live account and all of my details have changed so they wont be the same! can someone please help