First take a deep breath and be aware that the IRS is not always right ... next review the CP2000 notice carefully against the return you filed ... are they correct ? Did you miss any sales or basis ? Did they ?
Respond to the IRS timely either way ...
I GOT A LETTER FROM THE IRS
I AM BEING AUDITED
If you purchased Audit Defense:
FYI ... importing anything is not perfect especially if it was from a broker that puts out a corrected statement after you have filed. Also some uncovered sales do not always transfer which is why it is important to review everything before filing a return.