If you’re in the process of being audited, we highly recommend that you see a tax professional. Professionals who are licensed to represent you in an audit include tax attorneys, CPAs, and EAs. Even if you had filed your taxes with a tax preparer, the third-party designee on your tax filing can only answer questions about the tax filing on your behalf, not fully represent you in an audit.
Several tax filing softwares will have an option to pay for guaranteed audit protection. If you've paid for this service, then you should alert the company so that you can cash in on the feature.