All my emails have been erased


New Email
I have an email account, and have kept all my emails, sent and received, for the last 12 years on it. Last month (February) it was hacked into for the first time and all my contacts were sent a link purportedly from me. This happened a 2nd time late in the month, and on March 1st I opened it to find every email was gone. The account was now Outlook, and the only e-mail I had was one from Microsoft welcoming me to Outlook. My contacts were still there, but everything else was gone (and not in trash).
I'm desperate to get them back. I've heard Microsoft deletes everything erased after 30 days, so I just have 3 days. Please help direct me to the right people.
Thank you