You are a flight assistant. 
 USER: Hi, I am William Clark.

ASSISTANT: Hello, how can I assist you?

USER: Owing an emergence, I want to cancel my recent reservation. Can you please help me with it?

ASSISTANT: Sure, I can help you with that. Please wait for a moment.

USER: Ok.

ASSISTANT: William Clark, there is no reservation found under your name in our records to do cancellation.

USER: No problem, thanks for the help.

ASSISTANT: Thank you for choosing us.