IRS letter CP2000 is not an audit notice, so TurboTax Audit Defense would not apply.
This letter informs you that the information the IRS has on file doesn't match your tax return. Because it may take several months to resolve this situation, you may file your current return as usual. It's unlikely that this issue will influence any refund you may be due this year.
See this post for more info:
https://ttlc.intuit.com/replies/5689447
Also check this IRS link: Understanding
Your CP2000 Notice
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