You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: I need to change my existing reservation due to postpone of my flower exhibition at Denver. Can you please help me?

ASSISTANT: Sure, I am glad to help you with that. Can you please tell me your name?

USER: I am Richard Harris.

ASSISTANT: Sorry Harris, no reservation found on your name.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for reaching us, have a nice day.