First, make sure you have a secure email address that only you can access. Once you have this address set up, have this person assist you in accessing the account. After gaining access to your account, update your login email address information by taking the following steps:
Go to the Account Settings page listed in the Account drop-down menu.
Click "change" in the Email section.
In the "New Contact Email" field, carefully type your new email address.
Click the "Add New Email" button. You will then be asked to enter your password to confirm the requested change, and an email will be sent to this address containing a confirmation link.
Follow the instructions in the confirmation email to complete the process.
Once your new email is confirmed on your account, you can then go back to the Account Settings page to remove the email address that does not belong to you.