You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you today?

USER: I am Cynthia Parker. I am planning to attend business meeting at DEN, can you please help me with booking a flight ticket from PHX?

ASSISTANT: Sure, when would you like to depart and return?

USER: Sure, I would like to take off on Dec 16 and return on Dec 18.

ASSISTANT: Do you need halt in between your journey?

USER: Yes, I need a halt in between the journey.

ASSISTANT: Do you have any class preference?

USER: Yes, I prefer economy class.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Sorry, there are no flights found with your given dates.

USER: Ok, no issues. Thank you for the information.

ASSISTANT: Thank you for opting us.