You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: My name is Debra Wright. Can you please book me a plane ticket form LAS to DCA?

ASSISTANT: Sure, I will help me out. Please provide me your travel dates.

USER: Sure, my trip dates are from 05/01 to 05/03. Ok.

ASSISTANT: Sorry Debra, there is no flights in your route.

USER: It's ok, thank you.

ASSISTANT: Welcome, thank you for reaching us.