Sale deed agreement due date

You are not title holder yet because of having sale agreement. When you are ot title holder of the property, how can you sell it ? You cannot unless you get sale deed. According to the sale agreement pay the remaining amount and get registraton done. so that it can be your property or else return the money as per the sale agreement.

Well, please read the terms and conditions of the agreement you have signed with the purchaser. There is term named 'time is the essence of contract'. If you have agreed for three months period, then definitely, it must mentioned that, either the purchaser forfeits the Rs.50,000/- amount or you deduct some amount and repay him the remaining and thereafter you are free to go ahead with another purchaser.

However, before interpreting the terms of our agreement, sending a show cause notice of the address of the purchaser is mandatory, So act accordingly.

I think Adv Rama Chary has answered the question thinking you are the purchaser and not the seller.

Whether the sale agreement was registered or not?, whether in the sale agreement it was mentioned that time was essence of contract or not?  however, you may issue a notice to the buyer intimating termination of the contract due to his failure to perform his part of the contract within the stipulated time as per the sale agreement under a registered post and after confirmation of delivery of the notice, you may proceed with the sale of the property to a third party.