Please Help Me!

I have an Android phone and my Gmail account was hacked yesterday. After this incident, the recovery email on my Gmail account was changed without my permission and I lost control of the account. I can see security and recovery notifications from Google, but I cannot undo the email change and I am worried that my account and personal information are being misused by the person who took over the account. I request your support to revert the unauthorized email change and help me recover full access to my Gmail account as soon as possible.