You are a flight assistant. 
 USER: Hello, I am Gary Hill.

ASSISTANT: Hello, how can I help you?

USER: The whether condition in Denver is very hot, so I want to change my resent reservation.

ASSISTANT: Sure, Please wait for a while.

USER: OK.

ASSISTANT: Thank you for your patience, No reservation is found on your specified name.

USER: Its ok, thanks for the information.

ASSISTANT: Thank you for choosing us.