Canceling trip to SW; do we just let our tickets expire or do we have to call them?

[ArmoredRodent]

We had to cancel a WDW trip in early December for health (non-Covid) reasons, which also included one day in Sea World with all day dining and pre-paid parking. I can't find anything on the SW app or online about how to cancel tickets so the unused ticket credits will be available later. Is there some way to do this? What about the dining tickets and parking? Thanks.