You are a flight assistant. 
 USER: Hi, I am Amanda Lee.

ASSISTANT: Hello, how may I help you today?

USER: I want to change my existing reservation due to postpone my office meeting. Can you help me with that?

ASSISTANT: Sure, please let me check and let you know.

USER: Sure.

ASSISTANT: Sorry, unfortunately no reservation found with provided name.

USER: Ok, not a problem. Thanks for your kind service.

ASSISTANT: Pleasure to serve you, thanks for your interest.