You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am Michael Young.

ASSISTANT: Ok.

USER: I need change my recent reservation due to postponed of my exams.

ASSISTANT: Sure, Wait a minute.

USER: Ok.

ASSISTANT: Sorry to tell that there is no reservation found on your name.

USER: Thanks for your information.

ASSISTANT: Thank you for contacting us.