Tickets cannot be deactivated.
To avoid incorrectly activating a ticket, be sure that you have selected the correct ticket and that you are ready to board the vehicle.
Once activated, the ticket is valid for a predetermined period of time. Tap the Ticket Info button to see how long your active ticket can be used for travel.
If you have questions regarding compensation for incorrectly activated tickets, refer to the FAQs in the Help section of your app.