You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: My meeting got postponed. So, I  would like to change my existing reservation. Can you help me?

ASSISTANT: Sure, can I know your name?

USER: My name is Kimberly Green.

ASSISTANT: Give me a minute.

USER: Sure.

ASSISTANT: Sorry Green, there are no reservation matching with your details.

USER: That's fine. Not a big deal. Thank you for the information.

ASSISTANT: You are welcome.