I received a letter from the IRS regarding an error on my 2017 return. Do I have audit protection for that return so someone can look into it?

What type of IRS letter?  There should be a CP or LTR number in the right corner.

Did you purchase the optional Audit Defense package or MAX Benefits when you filed your 2017 return?  If so, we can tell you how to contact the company that handles that (intuit.taxaudit.com) .

If you did NOT purchase Audit Defense/MAX, you can contact the TurboTax free Audit Support Center for help with an IRS letter.   To get the phone number, go to the page at the link below, click the blue "Get Help" button, and follow the prompts.

https://support.turbotax.intuit.com/irs-notice/audit-support/

If you explain more about the type of letter and what the IRS is alleging therein, then you may get comments from other folks in this user community forum.   But this is a public Internet forum, so don't post any personal info.