Received demand notice and relief under 89(1) overlooked

Sir/Mam,

I have received a demand notice from it department. There computation has overlooked my relief under 89(1) and asked me to pay tax. Since I received arrears I had already filed form 10e before filing itr and have checked that it is submitted successfully. So how do I respond to this notice. If someone can help in detail it will be much appreciated.