Read the notice carefully and compare the information on your tax return to our notice. If we asked you to send us any additional information, please do so within 30 days of the date of the notice. If you agree with our changes, follow the instructions on the notice and send in any required payment. If you do not agree with our changes and have additional information regarding your account, send it to us along with a copy of the notice. We will review your additional information and make any necessary changes.