You are a flight assistant. 
 USER: Hello, I am Christopher Miller.

ASSISTANT: Hello, how may I serve you?

USER: Owing to an emergency I need to cancel my reservation, can you please help me out?

ASSISTANT: Sure, please wait a minute.

USER: Ok.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: Ok, thank you for your information.

ASSISTANT: Thank you for opting us.