You cannot correct and refile your return. When you received this letter from the IRS they normally make the adjustment and send you the adjusted amount. You do not have to do anything with your return unless you disagree with what the IRS has adjusted. If you disagree, the letter probably provides an area for you to respond and say you disagree and why you disagree. If you disagree, you could file an Amended Return.
The only reason you would amend your return at this point is if you disagree with the IRS and an amended return shows you a different outcome,
