Stamp duty@registration

Respected Sirs,

Government of Mahashtra has announced Amenesty Scheme for Stamp Duty @registration.

For my flat Which i purchased from the builder during late 1980 i have paid the Stamp Duty and penelty during 1994 Amenesty Scheme.But due to the wrong advice of the Agent and my ignorance of Registration law ,the instrument(agreement for for sale) was not submitted for Registration.

Now i want complete the Registration.But the Seller(Builder and Developer) is no more

Kindly advise me how i can complete the registration.

Best regards