If the rollover was an indirect rollover and the code on your Form 1099-R doesn't automatically reflect that it was a rollover, it is likely because TurboTax hasn't yet asked you the follow-up questions that will remove it from your taxable income.
TurboTax doesn't ask those at the entry of each 1099-R, but instead once the entire retirement income section has concluded so it can also check for any other exceptions to taxes and penalties.