IRS says I didn't file....

To access your current or prior year tax returns sign onto the TurboTax website with the userID you used to create the account - https://myturbotax.intuit.com/

Scroll down to the bottom of the screen and on the section Your tax returns & documents click on Show.  Click on the Year and Click on Download/print return (PDF)

There will be a Postmark Report included in the PDF download if you e-filed the tax return.  The report will show the date/time the tax return was transmitted and the date it was accepted by the IRS, if it was accepted.  If you printed and mailed the tax return then TurboTax has no way to know when or if the tax return was ever filed.

See this TurboTax support FAQ for accessing prior year online tax returns - https://ttlc.intuit.com/community/prior-year-return/help/how-do-i-access-my-prior-year-return/01/270...