You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you?

USER: Elizabeth Anderson here. Due to some reason, my event is postponed. Can you change my reservation?

ASSISTANT: Sure, please wait for a moment.

USER: Sure.

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

USER: Thank you.

ASSISTANT: Most welcome. Have a great day.