What is the best approach on recovering your login account if being hacked or logged in by different user

I'm a beginner in terms of UX. Your thoughts are highly appreciated. I love to discuss related to security with regards to a personal account on the mobile app that contains sensitive or important data/information.

Sample scenario

  1. What will you do if your account is hacked, changed the email address, and change password in a new one? What are the best ways for you to perform when you want to recover your Acc?

This my flow Idea for the problem:

  1. User can recover the account by putting the old email address (old email address will still be active but not visible on the app)
  2. After that user verifies it in the old email and creates a new password for security (Note: user don't need to type the current password)
  3. Old email will be back again on the app and disregard the new one.

Let me know your thoughts. Thank you!