While filing income tax return this year, you forgot to download and check the information in your AIS. Suppose there is an error in the AIS which has not been rectified by you, say interest earned from a bank account which was closed two years ago. Since the bank account has already been closed, you will not be earning interest. However, your AIS states that you have earned interest from that bank account during the FY, and it has been not disclosed by you in your ITR form. The tax department will send you an income tax notice with additional tax demand.