You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: I am Eric Lewis. I want to book a flight ticket from PHX to LAS. Could you help me in booking?

ASSISTANT: May I know your travelling dates, please?

USER: My travelling dates are from Nov 19-21.

ASSISTANT: Do you need any specifications for this reservation?

USER: My return time should be in the evening and I need connecting flight.

ASSISTANT: Please wait a moment.

USER: Ok.

ASSISTANT: Sorry, there are no flights running on your journey dates.

USER: Thank you. That's ok, no problem.

ASSISTANT: Thank you for reaching our service.

USER: Thank you for helping me.