You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. how can I help you today?

USER: My name is Nicholas Green. I have a plan to meet my brother in Atlanta, can you help me for booking a flight ticket from ORD to ATL?

ASSISTANT: Sure, can you please share your journey dates?

USER: My travelling dates are from 09/14 till 09/16.

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

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

ASSISTANT:  Welcome, have a nice day.