I have requested and entered the verification code 4 times and it keeps showing expired or incorrect, anyone know the problem?
Leave the window open that asks for the code; closing it will invalidate the code.
Open another tab or window or use a different browser to check your email for the code.
If you're using a mobile device, it's okay to open your email app or another tab in your browser. Just keep TurboTax open in the background and return when you've got your code.