You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I guide you?

USER: I need to book a flight ticket from LAS to LAX, Can you please help me for booking?

ASSISTANT: Sure, I can help you and can I know your departure and arrival planned journey dates?

USER: I would like to travel on 03/05 to return on 03/07.

ASSISTANT: Can I know your name please?

USER: Scott Perez.

ASSISTANT: Can I know your class preference?

USER: I need a economy class.

ASSISTANT: Please give me a moment.

USER: Sure.

ASSISTANT: I regret to inform you that there is no flight obtained on your specifications to book a flight ticket.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you for approaching us, have a nice day.