Non Execution of Sale deed of Residential Flat by the Builder

Sir, We had purchased a flat in the year 1991. We highlight below the main facts for your kind perusal : 1. We have the Bill raised by the Builder, showing the Cost of the Flat . 2. We had paid full amount of consideration against the above bill through A/c payee cheques. 3. Our payment had been duly Receipted and acknowledged by the Builder . 4. No written Agreement was made in our favour by the Builder at the time of purchase. 5. We are having complete possession of the flat since 1991. 6. We have the Assam State electricity connection in our name. 7. We are having Guwahati Municipal Holdings in our name. Now on our verbal approach and requests, Builder is adament to execute any sale deed, despite the fact that we are ready to bear any Registration expenses etc. We are very much mentally harassed and distressed for want of the sale deed. At the same time, we want to dispose off the flat also. Please advise. we shall be very greatful to you for your kind favour. With Regards