The 2019 AGI is found on your 2019 Federal tax return Form 1040 Line 8b
Or go to this IRS website for free federal tax return transcripts - https://www.irs.gov/individuals/get-transcript
For a fee of $43 you can get a complete federal tax return from the IRS by completing Form 4506 - http://www.irs.gov/pub/irs-pdf/f4506.pdf
If the IRS continues to reject your 2020 federal tax return due to an incorrect 2019 AGI, then enter a 0 (zero) for the 2019 AGI and e-file your tax return again.
