The IRS hasn't finalized one or more of your forms. Once forms are finalized, you will be able to access this section.

Try closing TurboTax, clear your Cache and Cookies if you are using TurboTax Online, and reopen TurboTax.  You can also try a different browser.

Also, make sure you have ran all updates. 

If you are using TurboTax Desktop, check for updates under the Online Tab.

[edited 2.9.24 | 11:39am]