It is impossible to e-file twice. The IRS will only accept one tax return with your SSN. Any other attempts to e-file will be rejected. If you somehow tried to file again, just watch your emails for the messages of acceptance or rejection. Do not try to change anything on your return now.
When you e-file your federal return you will receive two emails from TurboTax. The first one will say that your return was submitted. The second email will tell you if your federal return was accepted or rejected. If you e-filed a state return, there will be a third email to tell you if the state accepted or rejected your state return.
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