You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER: Can you help me booking a flight ticket from PHX to DEN?

ASSISTANT: Sure, can you share your trip dates?

USER: I will start on 05/04 and return on 05/06.

ASSISTANT: Do you have any specifications?

USER: I need a break in my journey.

ASSISTANT: May I know your name?

USER: I am Lisa Evans.

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

USER: No problem, thank you for the information.

ASSISTANT: Thank you for opting us.