You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, may I know your name please?

USER: My name is Angela Scott, I want to change my existing reservation due to postpone of my business meeting.

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT: Sorry, we did not find any reservation on your name.

USER: No problem, thank you for your service.

ASSISTANT: Thanks for reaching us.