Hi,.
user
Hello,  how may I help you?
assistant
As it's science festival please book a ticket from Washington to Denver.
user
Sure. May I know your good name?
assistant
My name is Michelle Phillips.
user
Let me know your depart and arrival dates.
assistant
Journey dates are from 03/23 to 03/25.
user
Do you prefer direct flight or connecting flight?
assistant
I prefer connecting flight.
user
May I know your boarding and landing points?
assistant
Ok. Airport codes are DC-DCA and CO-DEN.
user
Please, wait.
assistant
Sure.
user
Thank you for being patience, there is no connecting flight available with your given specified dates.
assistant
Thanks.
user
Thank you.
assistant