Delhi Development Authority [DDA] — regarding dda flat surrender

Address: Dda , vikas sadan new delhi, New Delhi, Delhi, 110023

I, richa verma, had been alloted dda flat 1 bhk in narela pocket g -7. I wish to surrender this flat. After filling up the cancellation form, and submitting it, i did not receive any notification for the same. Also i realised i attached the wrong document and there is no option to edit or delete it. I have been trying to contact the helpline number but my call is transferred from one person to another but still no one has any clue about sorting out the issue. Please help!