Try this work around:
1. Sign into your account.
2. Click on the My TurboTax menu and select Visit My Tax Timeline .
3. Under SOME THINGS YOU CAN DO click on Add a state. (You are not adding a state to your return. This allows you to get back into your return.)
Once you are back in your return, you can go into the Personal Info tab and correct your last name and proceed with filing as you chose.
