You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: My name is Steven Lewis, I want to change my reservation as my plan to visit New York is postponed. Can you change my reservation?

ASSISTANT: Sure, we will help you. Please wait for a while.

USER: Sure.

ASSISTANT: Thanks for your time, there is no active reservation found in your name to change.

USER: Ok, thank you for the information.

ASSISTANT: Thank you for choosing us, have a good day.