You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I am planning to watch sports live events in Washington, so please book a flight ticket from LAS to IAD.

ASSISTANT: Sure, may I know your planned travel dates please?

USER: I want to fly on Aug 25, return on Aug 27.

ASSISTANT: Would you like to travel in a connecting flight or a direct flight?

USER: I want direct flight.

ASSISTANT: May I know your good name please?

USER: My name is George Turner.

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

USER: Not an issue, thank you.

ASSISTANT: Thank you for approaching us.