Demolition of minor illegal construction after 9 years how to protect

Dear Sir/Madam GDA allotted Plot in 2003 in Indirapuram Ghaziabad to Mr. X. Mr X constructed three floor on same in 2007 and got compounding map approved from Ghaziabad Development Authority (GDA) in 2007 by paying requisite fees In 2007 Mr X sold first floor to Ms Y and Ground and Second Floor to someone else. In 2012 i purchased first floor from Ms. Y by Registered Sale Deed by taking Home Loan from HDFC Now in 2016 i.e. after 9 years from construction as well as approval of compounding map, GDA, on the complain of some neighbor is issuing demolition notice to me saying that Saft of the Building is small by only 10 inch and Rear Balcony (i.e. Backside Balcony) should be fully open. At present there is Jall of 4-3 and rest is covered by the roof and it is also fully open from the side of the wall. it all has been done/constructed by Mr. X in 2007 and i have done nothing. Grouand i have done nothing. Please suggest, what I should do.