Compensation against Acquisition of DDA Plot in Delhi

Hello, [DDA = Delhi Development Authority] My grandfather purchased a DDA plot in 1950's in Patparganj Area of Delhi which was acquired by DDA in 1970's. Plot registry is on name of my Grandfahter, he has expired in 2001 but before his demise he made my father the legal owner of all his property including this plot. So as of now my Father is a legal owner of this plot. We already hired some lawyer till 2002 to claim compensation or alternate Plot from DDA and lawyes also managed to get a latter from DDA in which they have stated that - They are willing to offer us a HIG DDA flat as a compensation but this communication happened in 2002. After that, due to the negligence of our lawyer (who has expired 2009) we could not progress on this case. Positives about this is that: 1. We do have a registry without any disputes on land. 2. Still the compensation is in treasury proving that we are not yet provided with any compensation. 3. We have letter from DDA stating that they are willing to offer us an equivalent HIG flat. My Questions are: 1. Can we still re-open this case to claim the compensation or alternate plot, after so long? As last communication with DDA/Court happened in 2002. 2. What should be the first step by us? 3. What is the quickest possible way to get this done? Regards // Nakul Sharma