You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Please help me to book a flight ticket from PHX to EWR.

ASSISTANT: Provide me with the travel dates please.

USER: My travel dates are from July, 19 to July, 21.

ASSISTANT: Is there any class preference?

USER: Yes, I need an economy class.

ASSISTANT: Is there any connection limit.

USER: I prefer a single connecting flight.

ASSISTANT: Are there any more preferences.

USER: I need to return in the morning.

ASSISTANT: May I know your name please?

USER: I am Betty King.

ASSISTANT: I regret to inform that there are no flights on your route with the given dates.

USER: No problem, thanks for your information.

ASSISTANT: Thank you for reaching us.