What does this mean "We reviewed your estimated tax penalty and found an error. Our correction to this error increased the penalty to $291? Turbo Tax calculated this num?

[donglenn777]

I paid estimated taxes based upon Turbo Tax calculation.

[Bsch4477]

How did the letter correct the penalty?  We can’t see your return. 

[donglenn777]

My estimated taxes for 2024 were calculated by Turbo Tax. I paid what Turbo Taxes told me to pay. Now the IRS is penalizing me for $291.

[baldietax]

did you pay ES quarterly and on time?  and did you pay ES for 2024 based on 100% of 2023 tax (110% if AGI > 150k) or 90% of 2024 tax?

TT 2023 would have generated ES vouchers based on 2023 tax by default and assumes your 2024 withholding will be the same as 2023; generally if you paid those on time you should not have a penalty unless some sort of adjustment to your 2023 tax happened which TT didn't know about, or you had less withholding.  But if you went thru the process in TT (Other Tax Situations / Form W4 and Estimated Tax) to estimate your income/tax for 2024 and pay 90% of 2024 tax due then it's possible the estimate changed.  IRS recalculates the penalty based on 2023/4 info and ES 2024 payments in their systems.  If your withholding was not at the level expected in the TT calculation this could also result in underpayment.

For the ES payments you can check your account at irs.gov to confirm the amounts and timings lined up with what was it TT for your filing.