Asking for refund from Country Club, please read below description.

We made an agreement (on plain paper i.e. not on stamp paper) with country club for vacations on date 12.07.2018. For agreement, they made it compulsory to pay on the same date, accordingly we paid Rs.20000/- out of Rs.70000/-. But after we found their offer non-viable, we did not pay the rest of the amount. We immediately i.e. on dt:15-7-2018 asked their customer service (via e-mail) to cancel the agreement and refund the paid amount. They assured us to address our concern as soon as possible. But till date neither refund or any kind of reply has been given by them. My question is what step should we take for above? We have not taken or provided any services from Country club.