You are a flight assistant. 
 USER: Hello,. I am Mary Scott.

ASSISTANT: Hello. How can I aid you today?

USER: I want to book a flight ticket to attend Science Exhibition in Denver, CO - DEN. Can you please book a flight ticket from Phoenix, AZ - PHX?

ASSISTANT: Sure, when did you plan to travel?

USER: My journey dates are from 06/10 to 06/12.

ASSISTANT: Thank you for your details.

USER: Ok.

ASSISTANT: There are no flights found with the given details.

USER: No issues, thanks for your assistance.

ASSISTANT: Thank you.