You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you for today?

USER: My scheduled examination dates has been postponed. So, I would like to change my existing reservation which is under my name.

ASSISTANT: Can you please provide your name to check whether your reservation is existed or not?

USER: Sure, my name is Kimberly Hall.

ASSISTANT: Sorry, there is no reservation found under your name.

USER: Ok, no issues. Thank you for checking.

ASSISTANT: You are welcome. Thank you for contacting us.

USER: You are welcome.