You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I guide you for today?

USER: Margaret Allen here. I want to book a flight from LGA to ORD, can you please help me in booking a flight ticket?

ASSISTANT: Sure, I am happy to aid you in flight ticket booking process. Can you please let me know your preferable travel dates for booking flight ticket?

USER: Sure, my travelling dates are from 10/16 to 10/18.

ASSISTANT: Please wait for a moment.

USER: Ok, take your time.

ASSISTANT: Sorry to say, no flight is available for you.

USER: That's ok, no problem. Thank you for the information.

ASSISTANT: Thank you for reaching us, have a nice day.