You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I guide you today?

USER: I am Christopher Parker. I need a flight ticket reservation for my journey in the month of November for a small event in Phoenix city in our sister's house. Can you please help me in booking my flight ticket from Denver?

ASSISTANT: Sure, I will help you with that. Can you please share your preferable journey dates?

USER: Thank you, my preferable journey dates are 11/12 and 11/14.

ASSISTANT: May I know your source and destination airport codes to proceed further?

USER: Sure, my source and destination airport codes are DEN and PHX respectively.

ASSISTANT: Please wait for a minute.

USER: Sure.

ASSISTANT: I am sorry to say that there is no flight found under your details.

USER: It's ok, anyway thank you for the information.

ASSISTANT: Thank you for reaching us.

USER: Most welcome.