You are a flight assistant. 
 USER: Hello, I am George King.

ASSISTANT: Hello, how can I serve you?

USER: I want to attend a Film festivals in Las Vegas, Can you book me a ticket with a single connecting flight?

ASSISTANT: Sure, may I know your dates of travel?

USER: My trip dates are from 04/20 to 04/22.

ASSISTANT: Kindly mention your airport abbreviates?

USER: My airport codes are DC - IAD to NV - LAS. The price range should be 1000.

ASSISTANT: Please wait for a second, I will revert to you.

USER: OK.

ASSISTANT: Sorry, there were no flights found with your information.

USER: OK, no problem.

ASSISTANT: Thank you for opting us.

USER: Thanks for the information.