Taxes Paid and Refunds: You get to see the taxes you have paid during the year and also the refunds received by you.
TDS on Sale of Immovable Property: If you have sold a property during the year, the TDS is deducted by the purchaser.
TDS on Rent of Property: If you receive rent over Rs.50K per month, the lessee will deduct TDS, which should be reflected here.
TCS on sale of Car: If the purchase price exceeds Rs.10L, you are required to pay 1% of the sale price as tax. The seller will deposit this amount to the Government Treasury.
High-Value Transactions: Any high-value transaction in your account in a bank or financial institution is reflected here.
Self Assessment Tax: Any advance tax paid by you during the year.
It is thus a summary of all your financial transactions and taxes thereon in the relevant assessment year against your PAN account. Information is updated every quarter. You are eligible to claim only those credits reflected in your Form 26AS while filing your ITR.
Once you have identified the errors, it is for you to get them rectified appropriately. The primary step is to bring the error or mismatch to the notice of your employer or deductor as the case may be. Your deductor can file a TDS correction statement to the Income Tax Department for rectification of the error. You can now also explain the reason for the mismatch in the portal in response to the query raised by IT seeking an explanation for the mismatch.