How do I finish a prior-year return that I started in TurboTax Online?

If you started your 2017, 2018, or 2019 return in TurboTax Online but weren't able to file it before the shutdown, you can finish and paper-file it in the TurboTax download software for PC or Mac.

Start by purchasing and downloading the software and install it on your computer. If you're also filing a state, be sure to download and install the corresponding state program (PC instructions | Mac instructions).

1. Now sign in at TurboTax.com using the same login you used to prepare your prior-year return.
   • If you don't remember it, try account recovery. Still no luck? Then just start over in the TurboTax software you downloaded and skip the rest of these instructions.
2. Under Your tax returns & documents, select Download .tax file (not the PDF) for the prior year you want and save it to your computer.
3. Back in the CD/download software, select Find a Tax File, and then browse to the tax data file you downloaded in the previous step.
4. Select the file and click Open.
5. You can now finish up in the software. Your return will need to be paper-filed, as e-filing prior years is no longer available.

https://ttlc.intuit.com/community/prior-year-return/help/how-do-i-finish-a-prior-year-return-that-i-started-in-turbotax-online/00/26322

I am retired and did not need to file in 2019. Now I can't e-file for 2020 because they have no AGI for that year.

@KathyMc Usually inputting 0 as your AGI if you did not file a prior year's tax return will work. If your tax return is constantly getting rejected due to your AGI, you will need to print and mail your tax return. You can follow the directions in this TurboTax FAQ to do so.