Hi Bernardo, welcome to planDisney!
The great thing about
Disneyland Resort theme park reservations is that Guests can make reservation changes themselves from within their
Disneyland Resort account! Reservations can be booked up to 120 days in advance, so if you are wanting to visit the Disneyland Resort in September 2022, your booking window would open in May 2022.
To cancel your current theme park reservation, you'll need to log in to your Disneyland Resort account, select the "My Disneyland" link, and then click the "Ticket and Reservation Details" link. Select the reservation you wish to cancel and click "Cancel Reservation". Once canceled, you're free to go ahead and book your new reservation (based on availability of course).
I do want to mention that there is an exciting event at
Disney California Adventure Park coming up. The
Disney California Adventure Food & Wine Festival is taking place from March 4, 2022 to April 26, 2022! This is an exciting event, filled with delicious food and beverage options, and super fun entertainment! If you're able to visit, you're sure to have a blast!
If you have to change your plans to visit during September 2022, that is also a great time, as Halloween Decorations typically go up throughout the Disneyland Resort during September!
Either way, I'm positive you'll have a magical time at The Happiest Place on Earth!
See ya real soon!
Jin