You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you for the day?

USER: I am Karen Young. I want to attend for an interview in Charlotte, so please book a flight ticket from PHX to CLT.

ASSISTANT: Sure, I will help you with this flight ticket booking. May I know your travelling dates, please?

USER: My departure day is Apr 19, return day is Apr 21.

ASSISTANT: Do you have any other specifications?

USER: I need a connecting flight.

ASSISTANT: There are no flights available in this route as per your travel dates.

USER: Ok, no problem. Thank you.

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