You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: I would like to book a ticket from DFW to PHX. Could you book a ticket?

ASSISTANT: Please provide your journey dates.

USER: Departure date is Apr, 21 and return is by Apr, 23.

ASSISTANT: Do you need any connection limit?

USER: I would prefer connecting flight.

ASSISTANT: Is there any other requirements?

USER: I would like to depart in the evening time.

ASSISTANT: May I know your name?

USER: My name is Catherine White.

ASSISTANT: There are no flights available on your routes.

USER: Thanks.

ASSISTANT: Thank you for choosing us.