Agreed with CP2000, now disagree

[drlrd]

I received a CP2000 notice for underpayment of 2016 taxes, agreed with the proposed changes and paid the amount of the bill.  Now I realize I should have disagreed and amended my return.  What do I do now?  

[SuziM]

Hi there!

If you now disagree, you can amend your return and include a copy of the CP2000 notice. You can get Taxpayer assistance with this https://www.irs.gov/help/contact-your-local-irs-office.