You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: As I am a doctor I want to attend for an emergency surgery at DFW. Can you please make a reservation from LAS?

ASSISTANT: Sure, can I know your trip dates?

USER: Sure, I want to depart on Feb 14 and need to return on Feb 16.

ASSISTANT: Do you have any specifications?

USER: I need a connecting flight which return in the evening time.

ASSISTANT: Can I know your name for booking your flight ticket?

USER: I am Daniel Carter.

ASSISTANT: There are no flights found on your specified travel dates.

USER: Ok, no problem. Thank you for checking.

ASSISTANT: Thank you for reaching us.