Demand raised by dept

Shweta Garg (CA FINAL Executive(Payables))   (147 Points)

12 April 2012  

I have got a demand for arrears (Rs. 1.37 Lakhs) from the income tax
department for the assessment year 08-09. As per the income tax web site
records, I can see my IT returns filed and acknowledged by the department. I
do not know why there is a demand. Can you guide me as to how I should seek
clarification from the department ?