You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: I am Thomas Gonzalez. I am planning to visit echo canyon trail & recreation area in Phoenix, PHX.

ASSISTANT: Sure, may I know your trip dates please?

USER: Can you help me to book a business class flight? My trip dates are in the month of December 24 and 26.

ASSISTANT: Can I know your source airport code please?

USER: My source is from Houston, HOU.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Thanks for waiting and sorry to inform you that there is no flight available as per your request.

USER: Ok, no issues. Thank you.

ASSISTANT: My pleasure.