How to tell turbo tax that my newly spouse did not file taxes last year?

[AmyW]

If a tax return was not filed for your spouse last year, then you can enter your spouse's AGI as $0. 

https://ttlc.intuit.com/replies/4231698

[mohamedabaker]

I have put $0, but the Federal and State tax returns were rejected and sent back due to this very issue. My spouse was claimed last year as dependent by her parents.

[AmyW]

If it won't accept 0 as the AGI, since the IRS no longer allows PIN numbers, you will want to print, sign, and file the tax return by mail.