You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, could you please tell us for what help you approached us?

USER: Please book a flight ticket from LAX to LAS?

ASSISTANT:  Sure, may I know your departure and arrival day?

USER: My journey dates are Apr 27 and Apr 29.

ASSISTANT: Ok, could I have your name please?

USER: I am Ryan Roberts.

ASSISTANT: Ok, do you need direct or connecting flight?

USER: I need a connecting flight.

ASSISTANT: Ok, do you have any other specifications?

USER: No.

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

USER: No problem, thank you for your information.

ASSISTANT: You are welcome, have a great day.