You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you at this moment?

USER: Can you please help me with changing the reservation?

ASSISTANT: Sure, may I know your name?

USER: My name is Elizabeth Taylor.

ASSISTANT: Please wait for a couple of minutes.

USER: Ok.

ASSISTANT: Sorry Elizabeth Taylor, no reservation done on your name previously.

USER: That's ok, thanks for the help.

ASSISTANT: Thank you for approaching us.