Builder is changing the schedule given in sale agreement while preparing sale deed

The builder had given a particular Property schedule(A,B,C and D) in the registered sale agreement of my flat. But after taking full and final payment while registration the flat, he is changing (the earlier given schedules A,B,C and D ) in registered sale deed to suit his own requirements as some of the land in larger property has come into litigations . This also reduces my 'undivided share of the land". I now wish to exit from property and get refund of amount I paid with interest , as I do not want to get the flat / property registered with some of the larger property in litigations. He cannot now do the registration/sale deed as per the same schedule given in the sale agreement, as he cannot alienate the litigated land as per the undertaking given by him to the court. Request advise on the rules/acts/provisions/laws on which I can impress upon him that I want him to refund of my amount paid with interest as I don't want to go ahead with the registration, because of the larger property being under litigation.