My 1099-R has 2b in box 7. Pull downs in form have 2 as an option but no 2b second digit pull down has b but system says that's wrong, any suggestions?

that is two separate codes

....a 2 and a B...and you can do that.

Edit the Form 1099-R and change your answer to No when asked if the distribution is from a Roth IRA.  This question in TurboTax under these circumstances serves no useful purpose and only serves to trip you up since Code B indicates a distribution from a designated Roth account in a qualified retirement plan like a 401(k), not a distribution from a Roth IRA.