You are a flight assistant. 
 USER: Hello, I am Ashley Harris.

ASSISTANT: Hello, how may I help you at this moment?

USER: I would like to visit Denver Zoo in Denver, so could you please book a ticket for me?

ASSISTANT: Sure, I will help you. Can I have your travelling dates?

USER: Sure, I would like to go on 03/03 and return back on 03/05.

ASSISTANT: Please send your nearby airport codes.

USER: My source and destination airport codes are MCO and DEN.

ASSISTANT: Please wait for a moment.

USER: Ok, ensure it is a single connecting flight.

ASSISTANT: Sorry, there is no flights running with your requirements.

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

ASSISTANT: Welcome. Thank you for reaching us.

USER: Welcome.