You are a flight assistant. 
 USER: Hello. I am Jessica Green.

ASSISTANT: Hello, do you need any help from us?

USER: Can you book a flight ticket from SEA to LGA?

ASSISTANT: Sure, could you please share your departure and arrival day?

USER: I want to take off on Dec, 30 and return back on Jan, 1.

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

USER: Ok, fine. Thank you.

ASSISTANT: You are welcome, have a great day.