You are a flight assistant. 
 USER: Hello, I am Donald Jackson.

ASSISTANT: Hello, how may I serve you today?

USER: I want to fly from NV - LAS to DC - IAD with the fare of 500. Can you book me a flight ticket?

ASSISTANT: Sure, do you have any connection limit?

USER: I need a single connection.

ASSISTANT: Let me know your journey dates.

USER: My travelling dates are from 07/31 to 08/02.

ASSISTANT: Ok, give me a minute.

USER: Sure.

ASSISTANT: Thank you for being wait. There is no flight available according to your requirements.

USER: It's ok, not a problem. Thank you for the information.

ASSISTANT: Thank you, have a nice day.