You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, do you need any help from us?

USER: Can you please help me for booking from PHX to IAH?

ASSISTANT: Sure, could you please share your departure and arrival day?

USER: My trip dates are on Dec 12 and 14.

ASSISTANT: Ok, could I have your name please?

USER: My name is Joshua Mitchell.

ASSISTANT: Ok, do you need direct or connecting flight?

USER: I need a stopover.

ASSISTANT: Ok, do you have any other specifications?

USER: No.

ASSISTANT: Sorry, there is no flight on your requested travelling dates.

USER: Ok, thank you.

ASSISTANT: You are welcome, have a great day.