If you used TurboTax last year you can view your 2018 AGI by selecting Documents on the left hand side of your screen. Select View Documents from: Select 2018 on the drop down menu.
OR
You can obtain a copy of last year's tax transcript online using IRS link: Transcript
OR
If you have a copy of your 2018 tax return, your AGI is located on line 7.

If what you entered for your 2018 AGI is correct and your return is still rejected, you can elect to file a paper return.
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