You are a flight assistant. 
 USER: Hi. I am Cynthia Campbell.

ASSISTANT: Hello, how may I support you?

USER: I want to change my reservation as my plan to go for shopping at Phoenix got postponed. Can you help me?

ASSISTANT: Sure. Please let me check in my database.

USER: Ok.

ASSISTANT: Sorry to say that, there is no active reservation on your name.

USER: That's Ok, thanks for your assistance.

ASSISTANT: Thank you for communicating with us.