You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: Margaret Walker here. I would like to change my recent reservation, can you help me with this?

ASSISTANT: Sure, please wait for a moment.

USER: Ok fine.

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

USER: That's fine, thanks for your information.

ASSISTANT: Thank you for approaching us.