When you use Turbotax Online version, you can prepare only one return per account/payment. This Turbotax help topic tells you how to start another return:
https://ttlc.intuit.com/questions/1894512-how-do-i-start-a-second-return-in-turbotax-online
That has been the case with Turbotax Online version for literally decades.
That is a fundamental difference between the Turbotax Online version, which you access through a web browser, and the CD/Desktop version which installs and runs on your home computer.
With the CD/Desktop version, you can prepare as many returns as you wish just for the price of the box.
When you use Turbotax Online version, you can prepare only one return per account/payment. This Turbotax help topic tells you how to start another return:
https://ttlc.intuit.com/questions/1894512-how-do-i-start-a-second-return-in-turbotax-online
That has been the case with Turbotax Online version for literally decades.
That is a fundamental difference between the Turbotax Online version, which you access through a web browser, and the CD/Desktop version which installs and runs on your home computer.
With the CD/Desktop version, you can prepare as many returns as you wish just for the price of the box.