After you file

@olingermv 

Just because you thought your return was correct does not mean it was correct.  Users make errors by leaving out income or entering data in the wrong places in the software, entering amounts incorrectly, etc. and it can take over a year for the IRS to catch the mistake.  Or the IRS could make a mistake, too.  

You do not tell us what your letter says, and TurboTax does not get any information from the IRS after your return has been filed.  No one at TurboTax knows about the letter the IRS sent you.

(what the letters from the IRS mean)

I GOT A LETTER FROM THE IRS   

https://ttlc.intuit.com/questions/3605673-i-got-a-letter-or-notice-from-the-irs

I AM BEING AUDITED

If you purchased Audit Defense:

https://ttlc.intuit.com/questions/2924451-i-bought-max-or-audit-defense-and-now-i-m-being-audited

AUDIT SUPPORT

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