If you have experienced an error after filing your return, you have to amend it accordingly. To be precise, the IRS often corrects mistakes on a specific tax return and may take returns without schedules. In these types of cases, there is no requirement to correct your return. But it is imperative that you file an amendment return in case there is an alteration in the filing status, credits, etc.
To claim a refund, you have to file a form numbered 1040X within 3 years after the date you filed your original return. You can also file it within 2 years after the date of paying the taxes. Note that the returns that are submitted before the date are regarded to be filed on the due date.
