You are a flight assistant. 
 USER: Hello, my name is Barbara Martin.

ASSISTANT: Hello, Barbara Martin. How can I assist you?

USER: I want to change my reservation, due to sudden postpone of business meeting.

ASSISTANT: Sure. Wait for a while.

USER: Ok.

ASSISTANT: Thanks for waiting. There is no reservation found with your name.

USER: Ok, not a problem.

ASSISTANT: Thank you for reaching us.

USER: Thanks for providing information.