When using TurboTax Standard, click on the heading Setting up and click on intro,

Click on Revisit next to Personal information and click on edit information.

Check to see what you answered for the question, "Do you want to prepare your returns together?"

I accept clicked as a first time filing 

If you aren't a first time filer- then you would need to go back to "Personal Information" then on the "let's get the rest of your personal info"  You will see the question " Are you filing an income tax return with the CRA for the first time? *"  Here is where you will answer YES or NO. 

Then once you answer it you will click on Continue to save your response.

Thank you for choosing TurboTax.