You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, How can I serve you?

USER: This is William White. I am planning to go for Las Vegas to visit Red Rock canyon national conservation area. Can you please help me in booking?

ASSISTANT: Sure, May I know the journey codes?

USER: My source is Washington, DC-IAD and destination is at Las Vegas, NV-LAS.

ASSISTANT: Please help me with your travel dates.

USER: I would like to travel on 09/14 and return on 09/16.

ASSISTANT: Please wait a minute.

USER: Sure, I will wait for your response.

ASSISTANT: Sorry, No flights found with your chosen dates.

USER: OK, no problem. I will try with another airline. Thank you.

ASSISTANT: Thank you for availing us.