Hi,
I has similar issue, but this worked out for me.
1) You will need your last year Self Sign PIN (you would have created 5 digit PIN for filling 2019 returns)
While again e-filling electronically once its rejected, there is a step which says "PERSON doesn't have 2019 tax return"(to enter AGI) - i forgot where exactly you will see this, but you would see it somewhere during the navigation of e-filling,
Then it gives an option of either a) physically mail the returns or b) enter the last year(2019) 5 digit Self Service PIN(Remember this is not IRS PIN) created while submitting the 2019 returns.
Thats it i remember my last years self service PIN and it worked for me. Both Federal & State returns were accepted.
This is just experience, not sure if this work for you.
Thanks
