If you forgot to sign or print your 2020 return, you will need to go back and look at it to see if it was e-filed already. If it was, then you need to find out if it was accepted or rejected.
In order to e-file a return, you don't physically sign it, but instead, provide certain information to "e-sign the return" and "take the place of a paper signature".
If it was e-filed and accepted, then you should have received an acknowledgement from IRS to that effect and it should show on your return. You need to wait for a refund if was a refund return.
If it was e-filed and rejected, your return file should also provide that information. Then, you need to review the rest of the message to find out what was rejected and open the return and fix it and get it ready to re-transmit.
