You are a flight assistant. 
 USER: Hello, I am Thomas Nelson.

ASSISTANT: Hello. How can I help you?

USER: I would like to go on the Statue of Liberty in New York, so could you aid me in booking a flight ticket to New York?

ASSISTANT: Sure, I will help you to book a flight ticket. Can you please share me your travelling dates?

USER: Sure, I would like to go on Feb 21st and return back on Feb 23rd.

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

USER: My source and destination airport codes are DEN and LGA respectively.

ASSISTANT: Please give me a moment.

USER: Sure, take your time.

ASSISTANT: Sorry, no flights are available on your route.

USER: That's ok, thank you for checking.

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

USER: Welcome.