What I feared might happen has happened. I was a paper filer my whole life until this year. And that's because my 2021 paper return (mailed and delivered in February 2022) was never processed. I did try to re-file it electronically at the end of last year once they said it was okay to do so if certain conditions were met but was told it was too late by Turbo Tax. So I never got my refund.
So this year when I finished the return and it asked me to put my last year's AGI, I felt like I still had to put the 2021 figure. But of course, there is no record of that because they never processed my return. I have no choice but to put the 2020 figure but wondered if there is any consequence of essentially skipping a year.
If it was rejected for AGI—-be aware that many 2021 returns took so long for the IRS to process that your 2021 AGI might not be in the IRS system. Try using zero instead.
If filing with zero is rejected then file again but select the option that you did not file last year. The IRS does not see that question and it will allow you to e-file with no AGI question.
https://ttlc.intuit.com/community/agi/help/where-do-i-correct-my-agi-in-turbotax-online/00/26311
If that does not work and you still cannot e-file, then print, sign, and mail your tax return.