If you don't know review your fees :
See this TurboTax support FAQ for checking your fees - https://ttlc.intuit.com/community/charges-and-fees/help/how-do-i-review-my-fees-in-turbotax-online/0...
If you purchased Audit Defense for your tax return, call TaxResources, Inc. at 877-829-9695, or report your IRS letter on their web site. http://intuit.taxaudit.com/ Do not contact the IRS until you have spoken to TaxResources. They may contact the IRS on your behalf.
If you did not purchase Audit Defense, you can get help with your IRS letter from TurboTax at the following link.
We can help you with your IRS letter
If you did not buy Audit Defense, we might be able to help you here. Tell us what reason the letter gives for why you owe money, and the notice number or letter number (starting with CP or LTR) at the top right. If the letter says there was something wrong or missing in your tax return, or proposes changes to the tax return, what exactly does it say?
Do not post any personal information or contact information. This is a public web site.
And what tax year are you referring to that the IRS is examining?
Also, if you happen to be a California filer that chose to pay TurboTax fees out of the Federal refund, then in California that payment method automatically includes "Premium Services bundle", which includes Audit Protection.