You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER: This is Kenneth Parker, can you help me to book a flight ticket from JFK to SFO?

ASSISTANT: Sure, can you share your journey dates?

USER: I am travelling from Sept 20 to Sept 22.

ASSISTANT: Do you have any preferences?

USER: Please ensure the book a departing flight ticket in the afternoon time.

ASSISTANT: Sorry, there is no flight on your given dates.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for reaching us.