Notice against air-002 code from it department-need help

Need Help on Urgent basis.........

My brother had got a Notice from Income Tax Department against non filling of Income tax return for A.Y 2013-14 (F.Y 2012-13) and also mention the code AIR-002 ( Credit Card Transaction >200000).

Ground of the case is that they have not filled the ITR due to non-taxable of income ( below 2 lacs) and also they have used his credit card for filling diesal for brother transport company lorry.

A per notice we have fill the online compliance in efilling portal but we want to know how we reply that in Income tax department regarding said case.

So please reply how we reply to income tax department and what documents will submit in IT department...