You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I succour you?

USER: I would like to change my reservation due to postpone of my engagement, please help me with changing.

ASSISTANT: Sure. May I know your name to check with the reservation list and get back to you.

USER: Reservation was done by the name Steven Williams.

ASSISTANT: Ok. It is unfortunate that there is no reservation found on your name.

USER: That's ok, thank you.

ASSISTANT: Thank you for picking us.