Hey, Kevin!
Welcome back to the Disney Parks Moms Panel! I am so glad you asked this question.
Anytime you want to make changes to an existing reservation when using a travel agent besides the Walt Disney Travel Company you will need to work directly with the travel agent. Please contact them with any changes you wish to make. There may be certain restrictions on your vacation package that your third party vacation planner will need to help negotiate on your behalfs such as adding a Disney dining plan, ticket upgrades or hotel changes. However, you may work directly with the Walt Disney World Resort when buying special event tickets, tours or other recreational activities because they are not part of a vacation package.
Disney Dad Tip: I have used Authorized Disney Vacation Planners for years and they are fantastic. Make sure they are giving you all the specifics about the time of year you are travelling. For example, September begins
Mickey's Not-So-Scary Halloween Party. You should be dying to attend this ghoulishly delightful swinging wake at Magic Kingdom Park. My favorite part is the
Happy HalloWishes Fireworks, it's sorcery in the sky.
Kevin, enjoy making many Magical Memories!
~Jason °O°