Cancellation of Sale Deed

My father is having a property(flat) in pune and it is proposed to be sell. As we get a client and ready for deal on a fixed amount. We got the token amount and submitted all documents to bank for Home Loan and for verification. Loan approved and DD issued in favour of seller and details of dd shared for registration. We have completed the registration process and balance payment done by the buyer. Now we submitted the documents to bank for disbursement of dd the raised objection on NOC issued by the Co-operative housing society. As bank said the NOC is not as per bank format so cannot issue the dd. We approached to society, Secretary of society said we are not concerned with bank. Society is concerned with the seller and can issue NOC related to member(owner/seller) and cannot take any responsibility regarding bank transaction or loan and not ready to issue NOC as per bank format. My questions are: 1. Is this deal is valid? As in Sale deed the mode of payment is mentioned but we have not received loan amount. 2. If bank and society stick with their rules then what will be the solution? 3. How we can cancel the registration or cancel the sale deed? 4. Now buyer can claim any ownership on the property? Are we safe from our part? 5. What are the legal formalities to be completed to cancel the above mentioned issue?