Hey there, Sopear, and welcome to planDisney!
If I'm understanding your situation correctly, it sounds like you currently have a
2-day standard theme park ticket where you can visit one park per day. However, there are two fun parks to visit at the Disneyland Resort (
Disneyland Park and
Disneyland California Adventure Park), so it also sounds like you want to spend time in both parks over the course of your two-day visit and you're wondering about the best way to do that.
Before I get to my suggestion, I wanted to also note that you currently need two things to enter the theme parks: (1) valid theme park tickets and (2)
theme park reservations for each day of your visit. Once you purchase your tickets then you're all set on the first part, and all that's left is choosing the specific park you want to visit for each day you've purchased tickets for.
Having said that, it is typically less expensive to purchase 2-day tickets rather than separate single-day tickets, so it does sound like you have made the best decision on your ticket purchase. In addition, you're only able to upgrade and pay the difference when it comes to ticket exchanges. There is not an option to downgrade tickets and get a refund on the difference after you've made your ticket purchase.
Beyond that, all that's left is to make your theme park reservations! The easiest way I've found to do that is by visiting the
Disneyland website, where you can hover over "My Disneyland" and select "My Plans." On this next page, you'll see all the details of your upcoming trip(s) including any theme park reservations. If you currently have both days set to "Disneyland Park" but want to switch one day out for Disney California Adventure Park, you can hover over the day you want to change and select the option to switch your reservation.
I know you have limited space to type in your question, so I hope I understood and addressed that correctly! However, even if it was a big ol' miss on my end, have no fear! You can always reach out to one of the wonderful
Cast Members at the Guest Information line who can help with the specific details of your situation.
Thank you again for your question, Sopear! I hope you have a fantastic time visiting the Happiest Place on Earth.
Have a Magical Day,
Greg