Hello. Brandon Parker, here.
user
Hello. How can I help you today?
assistant
I got a invitation from white house there is a event on 05/21 to 05/23, so I want to book a ticket.
user
That's great, let me know your airport codes.
assistant
My nearest airport is IAH, destination is IAD.
user
Please wait for a moment. Sorry, there are no flights available to IAD on 05/21.
assistant
It's fine, thanks for your information.
user
You are welcome.
assistant