You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I support you?

USER: My client meeting has been postponed, I want to change my existing reservation. Can you please help me with this?

ASSISTANT: Sure, we will help you out. Please wait for a while, I will check the status and revert you. Can I have your name to trace your details?

USER: Sure, I am Samuel Carter.

ASSISTANT: Thanks for your time, we are sorry to say that no reservation was found on your name.

USER: Ok, Thank you for your service.

ASSISTANT: Thank you for choosing us.