You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I just want to change my recent reservation because my business trip postponed, can you help me for that?

ASSISTANT: Sure, please wait for a while.

USER: Sure.

ASSISTANT: Can you please provide your name?

USER: I am Carolyn Adams.

ASSISTANT: Sorry Adams, there is no reservation found with your name to change.

USER: It's ok. Thanks for your helping me.

ASSISTANT: Thank you for approaching us.