You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you today?

USER: I am Joseph Martinez.

ASSISTANT: Yes Joseph.

USER: I want to book a ticket from New York to Denver to visit Denver Zoo, can you help me?

ASSISTANT: Sure, I will help you with that, please share your airport codes?

USER: I am departing from New York LGA airport and land in Denver DEN airport.

ASSISTANT: Can you share your travelling dates to proceed further?

USER: I am departing on 08/17 and return on 08/19.

ASSISTANT: Joseph sorry for the inconvenience, no flights as per your details.

USER: That's ok, thank you for your help.

ASSISTANT: It's my pleasure, have a nice day.