Someone will probably be along to comment generally that the TT tax penalty is only an estimate so adjustments can happen by the IRS.
But, I'm interested in the details why this happens as the calculation on Form 2210 is pretty straightforward, so I am not sure what's an 'estimate' about it unless something gets adjusted and the IRS recalculates it based on their own data on your tax/payment history - either the IRS determined a lower safe harbor amount because your 2023 tax liability was incorrect in TT, or your 2024 tax liability was adjusted, or your 2024 estimated tax payment dates were not correct in TT? (assuming you didn't adopt Annualized Income method, that's more complicated).
if you have more context on your underpayment situation that may be helpful to share - in desktop TT you should be able to see the calculation in Forms mode by double-clicking the penalty then double-click again in the 1040 worksheet to show the Form 2210. Does IRS send a revised 2210 back with the details how they calculated it differently to TT, or just give you $.
