Plot sold without permission from registered society

Sir, I am working in IAF as an Officer. I had purchased a plot from Air Force naval Housing Board which is a Co- Operative Society. There was no restriction put in the sale deed in which an Absolute sale was mentioned. Later an Association was formed locally by the plot owners. They placed a restriction on all plot owners not to sell their plots to any civilians out side Armed Forces. I considered it ultra wires as it is against the Constitution of India and illegal restriction of freedoms given by the CMDA(Chennai Metropolitan Development Authority) as the seller(AFNHB) didnot place any such condition in the sale deed. So I divided the plot into two as it was 3800 sq ft and sold to outsiders in 2013. Now in 2018, the local association filed a case in a local court to nullify the sale. Sir, can I know as to what is the Law in this regards.