You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Donald Scott.

ASSISTANT: How can I assist you?

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

ASSISTANT: Sure, I can help you. Please wait for a while.

USER: Sure.

ASSISTANT: Donald Scott, there is no reservation found under your name to do cancellation.

USER: No problem, thanks for checking.

ASSISTANT: Thank you for choosing us.