I can only reproduce the symptoms you are seeing by marking the IRA/SEP/SIMPLE box on TurboTax's 1099-R form, so it seems likely that you mistakenly marked that box. Make sure that the IRA/SEP/SIMPLE box is not marked.
Note that TurboTax's Smart Check will catch this error if it's present when the check is done.
Otherwise, delete and reenter the Form 1099-R.
