You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: I would like to change my reservation due to postpone of my sister's engagement.

ASSISTANT: May I know your name?

USER: I am Nancy Evans.

ASSISTANT: Ok, please wait.

USER: Ok.

ASSISTANT: There is no reservation found on your name.

USER: Fine, thanks for the response.

ASSISTANT: Thank you for opting us.