BUILDER Not giving NOC

I (Say owner 2) had done the agreement to sale with a buyer(Say owner 3) to sell my commercial office which I purchased 1 year back.The developer is not issuing me the NOC saying that unless the owner 1 gives me the old VAT payment against the purchase of 2007 he will not issue the same.Now my problem is that I can't execute deed of assignment unless the developer gives me NOC as its the condition of financial institute.I had committed 15 days only.What should I do to get  the NOC  fast and  legally within 7-8 days ?

When I purchased it from the person(Say Owner 1) who actually purchased from the developer/builder.While puchasing the office the builder has given NOC to him for the transaction.