First review the notice and your return carefully ... is the IRS correct ? If they are was it a data entry error that you made as opposed to a calculation error by the program ?
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/
