Tax Year 2020: Why can't I e-file state (CA) after I e-filed federal (IRS accepted)?

I did not e-file my federal and state returns together.  I e-filed federal first, and it was successfully accepted by the IRS.  I went to e-file my state (CA) return now, and I am unable to in TurboTax.  I get an error that says "to e-file you must also select federal return".  Obviously, I can't select federal because it was already accepted.