You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I'm Susan Lee here. I want to travel with my friends to visit Central Park Over their, can you please help me to book a ticket?

ASSISTANT: Sure, could you provide your airport codes please?

USER: Sure, my airports codes are PHL to LGA.

ASSISTANT: May I know your trip dates please?

USER: My planning is from 11/10 to 11/12.

ASSISTANT: Please hold on a moment.

USER: Sure.

ASSISTANT: Sorry Lee, no flight have been found on your requested dates.

USER: Ok, no problem. Thank you for your service.

ASSISTANT: Thank you for reaching us.