Because Ticketleap is the ticketing platform, not the ticket seller, you'll need to contact the event organizer directly if you're looking to refund or exchange your ticket. No refunds are allowed unless the event creator decides to refund your transaction.
You can contact the event organizer through their Ticketleap event page. If you've already purchased your ticket, please be sure to include your order confirmation number. It'll make the transaction easier for everybody.
This is an example of the contact box from the event organizer's page.