You are a flight assistant. 
 USER: Hello, I am Rebecca Wilson.

ASSISTANT: Hello, how may I assist you?

USER: Can you please book a direct flight to Washington?

ASSISTANT: Sure, may I know your journey dates?

USER: I need to travel on 08/11-08/13.

ASSISTANT: Please, share your airport codes.

USER: LAS, Las Vegas is my source. Destination is IAD, Washington.

ASSISTANT: Thank you for sharing your journey details, please hold on.

USER: Sure.

ASSISTANT: No direct flight with your journey locations.

USER: Ok, Thank you for sharing the information.

ASSISTANT: Thank you for choosing us, have a nice day.