there is no right answer because if you mailed in your return yours could be among the 2 to 3 million that the IRS has not yet processed. if you mailed the return and payment check together then the IRS should have your return. Does the notice contain an address to send your return? since you owed and the IRS cashed the check sending in another copy MIGHT be the thing to do. this time use a mailing service where you can get proof of delivery. see if others who respond to this thread have other advice.
