You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I am Justin Lee. I had planned to go on a vacation, but it was postponed due to some reasons. Can you change my recent reservation?

ASSISTANT: Sure, please wait for a moment.

USER: Sure, take your time.

ASSISTANT: Sorry, there is no active reservation found on your name in our database to change.

USER: That's ok.

ASSISTANT: Thank you for reaching us.

USER: Anyways, thank you for your help.