I have two identical accounts: Bob&Ulla and bob&ulla. I want to delete the bob&ulla account. They both seem to have my 2015 tax return which is the only time I used turbotax

Hi,

There is no option to delete your account. Once you've paid or registered, we're required to store copies of your return. Just  let the unwanted account go dormant. You can also clear your information from the account using the "Clear and Start over" feature. 

For further information you can refer to the following link:

https://ttlc.intuit.com/questions/1899886-can-i-delete-my-tax-return-in-turbotax-online