If you chose to pay with your Rio 2016 Virtual Payment and want to cancel tickets, you do not need to finalize and insert you payment information within the Rio 2016 Tickets website. If you chose as payment Visa credit card, upon receipt of e-mail with the result of the tickets on August 4th, 2015 , you have until August 9th to cancel your tickets. You must call to request the cancelling via e-mail or sac@tkthelp.rio2016.com of the Rio 2016 Customer Service at number 3004-2016, that works from 08:00 to 21:00 from Monday to Saturday (Brasília time).