After you file

I was due to receive a refund on my 2019 return and filed it late. Return was mailed on 1/18/2021. It is now 2 months later. I contacted the IRS and was told things are backed up months, especially mail-in paper returns. I attempted to e-file my 2020 return and it was rejected due to the AGI security check.  The IRS has yet to record my 2019 AGI! I am reluctant to mail in the 2020 return because it will obviously enter the same abyss as the 2019 return. Suggestions?