TurboTax software does not allow you to designate your 1099-R information as a designated Roth account. It only assumes that it is a Roth IRA. Therefore, it shows at B2 code in box 7 as an invalid code
In the questions that follow entering the code B2 Form 1099-R details, you must answer No when asked if the distribution was from a Roth IRA. It's a trick question since the code B already indicates that the distribution was from a designated Roth account in a qualified retirement plan, not a distribution from a Roth IRA. Edit the the Form 1099-R and correct your answer to this question.
Using Turbotax 2020, I couldn't enter B2 in for Box 7. So I entered B. After that turbotax didn't ask me if it is Roth IRA. Please specify where in the form to enter that. Thanks for your help.