e-file a previous year's return.

I electronically filed my tax returns for 2019 in October, 2020.  The returns were received and accepted as per TurboTax.  Obviously, this was all done during the height of COVID so communication with IRS was practically non-existent.  I have since tried multiple times to contact and get an update on the status of my taxes and my expected refund.  Throughout the process, I received many different reasons and explanations for the delay but there was one constant.  I was told not to re-submit my return.  Until today.  The agent admitted that they do not have my return and that I should resubmit my return, electronically.  Finally, an answer and a direction of what to do.  Unfortunately, I cannot find a way to electronically file a prior year's return.  Any suggestions?