You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I aid you for today?

USER: I want to change my existing reservation owing to an emergency.

ASSISTANT: I am here to help you about that. Can you please provide your name for checking the reservation status with your name?

USER: My name is Matthew Walker.

ASSISTANT: I am really sorry to say this Matthew Walker, there is no active reservation with your name for changing your reservation.

USER: Thank you.

ASSISTANT: You are welcome, thank you for reaching us.