When trying to e-file I get this error message, Your transmission didn't go through We could not e-file your return for the following reason:Duplicate SSN? Impossible.

[steveo59]

I haven't filed yet, so there can't be a return with the same SSN.

[docenaa]

This had happened to me years ago. I ended up mailing my tax return and for the following few years until IRS gave me IP PIN for each tax year. Apparently somebody filed a tax return using my SSN before I did, that is, identity thief.  So, you may have to print and mail your tax returns.

[Bsch4477]

Did you file previously for the stimulus?