I received a letter from the IRS that my return was incomplete. They did not receive my w-2.

If you entered the 2019 W-2 into the TurboTax program for the 2019 tax return then that tax data was sent with the tax return to the IRS.

It may be that the IRS has not received the employer copy of your W-2.  Or you entered a W-2 that was not file tax year 2019.

Download the PDF of your tax return using Print Center and choose the option for all worksheets.  There will be a Wage and Tax Statement worksheet included in the PDF if you entered a W-2.

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

When you sign onto your online account and land on the Tax Home web page, scroll down and click on Add a state. 

This will take you back to the 2019 online tax return.

Click on Tax Tools on the left side of the online program screen.  Then click on Print Center.  Then click on Print, save or preview this year's return.  Choose the option Include government and TurboTax worksheets

Follow the instructions provided by the IRS on the notice your received for what you need to do.