You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you today?

USER: Please help me to change my recent reservation.

ASSISTANT: Sure, may I know your name for the changing process?

USER: Michelle Harris.

ASSISTANT: Thank you, please wait for a minute.

USER: Sure.

ASSISTANT:  Sorry, we couldn't find a reservation on your name to change.

USER: Thank you for your information.

ASSISTANT: Welcome, thank you for reaching us.