You will be redirected to a Retry booking page, where you can either click on "Retry" Booking button or click on "Refund" button.
Also a customer care executive will try to get in touch with you on the number you used for booking your ticket to book your ticket. If in case the same price ticket is not available, full amount will be refunded back to the payment mode you used while booking your ticket. (Bank Account/ goCash, etc