It seems that you might be making entries in forms mode. Making entries in forms mode, particularly on TurboTax's 1099-R form, is prone to error. Errors resulting from entries in forms mode are not covered under TurboTax's accuracy guarantee.
Make the 1099-R entries only in step-by-step mode under Wages & Income -> Retirement Plans and Social Security -> IRA, 401(k), Pension Plan Withdrawals (1099-R) and answer the follow-up questions. I suggest going there, deleting the existing Form 1099-R and reentering it.
