If TurboTax agrees they were in error under the 100% Accurate Calculation Guarantee, they supposedly will reimburse penalties and interest if notified within 30 days of your receipt of your letter/notice..
See this FAQ which also has a form to submit an online claim. At the bottom of the FAQ are links to the "fine print" for the guarantees.
https://ttlc.intuit.com/turbotax-support/en-us/help-article/intuit-account-billing/submit-claim-turb...
If you need to speak to TurboTax Support:
