Hi Marcela,
Thanks for reaching out! Tickets added to an event or other post type will be listed in reverse order from when they were added, meaning that the last ticket added will be at the top of list on the front end. As there’s no way to automatically sort tickets or group them by type, I’d suggest adding your tickets in reverse order to ensure the proper display on your event.
If you’re interested in seeing more ticket sorting and reordering options added to Event Tickets Plus, we’d be glad to get your feedback over on our UserVoice forum–please don’t hesitate to pay us a visit over there and submit your suggestions for future updates!
Thanks again, and let us know if you should have any other questions!