You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello. How can I abet you?

USER: Please change my existing reservation.

ASSISTANT: Sure. Can I have your good name?

USER: I am Helen Adams.

ASSISTANT: Please wait a while.

USER: Sure.

ASSISTANT: Thanks for waiting, no reservation found on your name.

USER: Thanks.

ASSISTANT: Thank you for approaching us.