why is the income tax department sending you sms

why is the Income Tax Department sending notices or SMS asking you to login and check the Income Tax Department is get collecting information from registration department from banks from credit card companies and based on this information there updating the same in your pan login and on ce this is updated the computer system or Income Tax Department sending you SMS to check what information they have about you and they want you to file the tax return covering this information covering what details they have example if you have sold any property then you are return what you are filing should show sale of property and then should show all the capital and calculation so don't take this easily you need to do that