Hi Marcianne and welcome to planDisney!
Walt Disney World is such a magical place to celebrate a birthday! No doubt your son is going to have a great day at
EPCOT next month.
When purchasing a 1-day ticket to a park, you must designate which park you will be visiting at the time of purchase and a
theme park reservation is automatically made for you. The exact verbiage under "Important Ticket Details" on the purchase page says, "If you purchase a 1-day ticket with admission to one park per day, a park reservation will be made for you. The reservation is only valid for the date and park purchased. If you modify your date or park, a new reservation will be made for you." If you go back in to make a reservation on a day you already have a reservation, the calendar will show no availability for that park, which is what you could be seeing since your EPCOT reservation was already made.
If you purchased a multi-day ticket, you must make your own theme park reservations. Walt Disney World suggests that you look at the
theme park availability calendar prior to making your ticket purchase to make sure the parks you're interested in are available. Looking at the theme park availability calendar for August 21st, all parks are currently green which means they are all open to book and none are blocked out. If you have multi-day tickets, make sure they are properly linked to your account, assigned to each Guest and then try to make your park reservations again.
To view your upcoming plans, log in to your Walt Disney World account online and click on "
My Disney Experience" on the top right. Any plans you have made, including park reservations and
dining reservations, will populate on this page. If you are still having trouble or run into an issue, I suggest
giving a friendly Cast Member a call or use the online chat feature with a Cast Member, who can access your account and help you further.
Please stop back by if you have any additional vacation planning questions.
Have a magical day!
Leslie