You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, what can I do for you?

USER: I am Patricia Jackson. I need to book a flight ticket from PHL to JFK, can you please help me to book a flight ticket?

ASSISTANT: Sure, may I know when are you planning this trip?

USER: My trip dates are 07/07 to 07/09.

ASSISTANT: Please let me know if you have any specific preference during your flight journey?

USER: I need a halt. My price is 500.

ASSISTANT: Thank you for details. I am sorry to inform you that there is no flight available for your trip.

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

ASSISTANT: Thank you.