You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how can I help you?

USER: Can you please help me in changing my existing reservation, as my exam got postponed.

ASSISTANT: Sure, may I know your name?

USER: Myself, Gregory Moore.

ASSISTANT: Ok, please wait a minute.

USER: Ok.

ASSISTANT: Thanks for waiting, there is no active reservation on your name.

USER: Ok, no issues, thank you for your information.

ASSISTANT: Thank you.