You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Richard Clark. I am planning to book a ticket from PHL to LAX. Can you please help me out?

ASSISTANT: Can you please tell your travelling dates?

USER: I would like to travel on 07/14 and return back on 07/16.

ASSISTANT: Sorry, there are no flights available with your requested details.

USER: That's fine. Thank you for your service.

ASSISTANT: Thank you and have a nice day.