Hi everyone, thank you for all of your responses. I figured out what I was doing wrong. As I already paid taxes on the Traditional IRA contributions, and hence non-deductible, I needed to choose the rollover option in Turbo Tax, NOT the conversion option, for reporting the subsequent transfer of those funds from my Traditional IRA to my Roth IRA (backdoor Roth). That cleared the additional tax and penalty that was previously being shown when I had been reporting it incorrectly as a conversion.
