You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I want to change my reservation due to postponed of my semester exam, so please help me.

ASSISTANT: Sure, may I know your name?

USER: Sure, I am Matthew Hill.

ASSISTANT: Wait a minute.

USER: Sure.

ASSISTANT: Sorry, there are was no reservation found on your name.

USER: No issues, thank you.

ASSISTANT: Thank you for reaching us.