Delhi Development Authority [DDA] — sewage ghushing into my flat

Address: FLAT NB. 617 SANJAY ENCLAVE NEAR GTK DEPOT, New Delhi, Delhi, 110033

I am residing in lig flats of jahangirpuri and there is a flat besides my house which has not been alloted to any one. Some times back dda constructed it and now all its drainage passages are blocked although house is full of fecal waste. It is rotting and breading mosquitoes and flies. No one is helping us regarding the same kindly help us. As toilet water is ghushing into my flat also it is causing foul smell.