Hello Hnu,
Thanks for visiting Disney Parks Moms Panel with your question.
While I'm sorry to hear that you didn't visit the Walt Disney World theme parks to use up all your ticket days, I do hope you enjoyed lots of magic in the parks when you did visit. There's always so much to see and do and experience in a Walt Disney World vacation both inside the theme parks and all around the Resorts.
Unfortunately, as I don't have all the details on the types of tickets you bought or how you used them so far or whether you're still at Walt Disney World, I don't have a lot of specific guidance to offer. In general, tickets are nontransferable and nonrefundable. Redeeming a Walt Disney World theme park ticket for a Disneyland Resort theme park ticket would not be an option. If the tickets you purchased are multi-day tickets, they will need to be used within 14 days of their first use. If you are still within the 14-day use time frame and still at Walt Disney World, you could explore upgrading to a
Disney Premier Passport that includes admission to both the Walt Disney World Resort and the Disneyland Resort. You'd need to upgrade your tickets in person at a
Walt Disney World Guest Relations and Ticketing center.
Hnu, I'm sorry I don't have more options to suggest for you. If there are additional questions you have, you can reach out to either Walt Disney World Resort Ticketing at (407) 566-4985 or Disneyland Resort Guest Information and Ticket Sales at (714) 781-4565.
Here's wishing you lots of Disney magic in your vacations ahead.
Jerry