You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I help you?

USER: I want to change an existing reservation, so please help me in changing the reservation.

ASSISTANT: Sure, May I know your name?

USER: Myself Gary Hall.

ASSISTANT: Ok, please wait a minute.

USER: Ok.

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

USER: Not an issue. Thank you.

ASSISTANT: Thank you.