You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you at this moment?

USER: My name is Helen Lewis, I want to book a flight from LAX to meet my uncle. Can you book a flight to IAD?

ASSISTANT: Sure, I will help you. Please send your travelling dates.

USER: I will travel on Oct 26 and return on Oct 28.

ASSISTANT: Do you have any preferences?

USER: I need a flight with single connection.

ASSISTANT: Sorry, there is no flight available on your journey dates.

USER: Ok, thank you for the information.

ASSISTANT: You are welcome, have a nice day.