The IRS has rejected your return because the 2020 Adjusted Gross Income - AGI - or self selected PIN you entered as an identification method on your 2020 Tax Return does not match IRS AGI records.

How do I fix e-file reject IND-031-04 or IND-032-04?

https://ttlc.intuit.com/community/rejections/help/e-file-reject-ind-031-04-or-ind-032-04-the-agi-or-self-select-pin-from-last-year-doesn-t-match-irs/00/25809

Did this code cause my 2021 return to be

rejected by the IRS?

@SS1961LS  No one here can see your return.  If your return was rejected for your 2020 AGI then enter a Zero for the 2020 AGI.  

When prepare and eFile your 2021 tax return, your 2020 Adjusted Gross Income (AGI) is used to validate your identity and to sign your return.

Attention: Did your IRS Return get rejected by the IRS even though you did enter the correct 2020 AGI?

The number of 2021 Tax Return rejections by the IRS - not eFile.com - has increased this year over previous years, even though the 2020 Adjusted Gross Income amount was entered correctly by the filing taxpayer.

Problem: The IRS has rejected your return - not eFile.com - because the 2020 Adjusted Gross Income - AGI - or self selected PIN you entered as an identification method on your 2020 Tax Return does not match IRS AGI records. Another reason, why your return got rejected could be because you entered the question on whether you filed a 2019 return incorrectly. 

Here's a link to help you... 

https://www.efile.com/tax-service/tax-return-rejection-codes/ind-031-04/