Section 154 under the IT Act of India, 1961 deals with the rectification of the mistakes that might have happened in the official records of income tax or because of any mistakes occurred in any order that is passed by the Assessing Officer. The rectification order that is issued by the tax department is either because one has filed a rectification request and the Income Tax department is responding to that or the tax department has taken action on its own motion when a discrepancy has been identified by them for the processing of income tax that they did for any tax payer.