You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: My business trip has been postponed.Can you please help me for changing the existing reservation?

ASSISTANT: Sure, may I know your name please?

USER: Sure, I'm Laura Garcia here.

ASSISTANT: Laura Garcia, there is no previous reservation with your details.

USER: Ok, no issue.

ASSISTANT: Thank you for approaching us.

USER: Thank you.