How do i close my account? i have two accounts and one was created erroneously

For the account you do not want, I suggest you "Clear and Start Over" first to delete all your information. 

Then simply leave it. There is no true way of "Closing an account" but it will become just a blank spot in the cloud with no information in it. 

Clear and Start Over is in Tax Tools on the left side-bar. 

How to Clear and Start Over

Thanks for responding. Alternatively, how do i merge the accounts? I cant change the email address on the "primary" account

TurboTax online accounts cannot be combined or merged. To change your address in your "primary" account with TurboTax, open  your account and select My Info in the left hand panel.  Scroll down to the section Mailing address select edit to change your address.