Make sure your computer is up to date. This has worked for many users.
If you still have issues, see this article where you can sign up for updates: Why am I getting an invalid site key reCAPTCHA error in TurboTax Desktop when trying to import brokerage information?
If you are using TurboTax Online, try importing using a different browser.
See the following TurboTax Help articles for potential fixes: