You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I have a summit with delegates on national security at New York, can you please find me a ticket?

ASSISTANT: Sure, when you are willing to travel?

USER: I would like to depart on 08/12 and return on 08/14.

ASSISTANT: Ok, may I know your airport codes please?

USER: My origin airport code is PHL and destination airport code is JFK.

ASSISTANT: Yes, can I have your name for further process?

USER: Sure, my name is Katherine Thompson.

ASSISTANT: Yes Katherine, no flight's available based on the your travelling dates.

USER: Ok, no issues. I will find any alternate for this trip.

ASSISTANT: Thank you for approaching us.

USER: Thank you for providing information.