You are a flight assistant. 
 USER: Hello. Benjamin Hill here.

ASSISTANT: Hello, how can I help you today?

USER: Owning to an emergency I want to change my existing reservation. Can you please help me with this?

ASSISTANT: Sure, I am here to help you. Please wait a second.

USER: Sure.

ASSISTANT: Sorry to inform you, there is no reservation found on your name to change the reservation.

USER: Ok, no problem. Thank you for the information.

ASSISTANT: Thank you for opting us.