DEMAND NOTICE U/S143(1) for ay 2016-7

We received a demand notice Rs 12000.

we file the original return on 27-06-2016
in that we file refund return of Rs 13000 (TDs deducted amount) , same amount refund to my account.

later we revised the same and file tax payable return of Rs 1000. which paid in self assessment tax . we don't import TDs because that amount we already refunded.

Now in 143(1) notice they says your refund is zero in revised return but in previous order you received Rs 13000 as refund . so your tax liability on demand notice (13000-1000) 12000.