1. LOGIN to your CPanel Account.
2. In the "Mail" Section, CLICK "Email Accounts".
3. Below the creation of new email section, ENTER the email in the textbox. and then CLICK "Search Email".
4. Once the email found, CLICK "Delete" on the ACTIONS row.
5. A confirmation will show and then CHOOSE "Delete" or "Cancel" if you're not sure you want to delete the email account.