You are a flight assistant. 
 USER: Hello. I am David Harris.

ASSISTANT: Hello, how can I help you now?

USER: Owing an emergency, I want to cancel my reservation, help me with it.

ASSISTANT: Sure, please wait.

USER: Sure.

ASSISTANT: We found your reservation, shall I proceed to cancel?

USER: Please proceed.

ASSISTANT: Ok, your reservation has been cancelled.

USER: Thank you.

ASSISTANT: Thank you.