You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you at this minute?

USER: Can you please help me to book a ticket from LAX to PHL?

ASSISTANT: Sure, I am happy to help you with that. Can I know your planned trip dates?

USER: I want to start on Sept 16 and return on Sept 18.

ASSISTANT: Do you have any other requirements?

USER: I want to return in the afternoon.

ASSISTANT: Could you provide me your name?

USER: Samantha Allen here.

ASSISTANT: Sorry to say that, there are no flight's available based on you travelling dates.

USER: Ok, not an issue. Thank you.

ASSISTANT: Thank you for approaching us.