You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello, how may I amend you?

USER: I am Dennis Smith. Owing to an emergency, I want to cancel my recent reservation. Can you help me?

ASSISTANT: Sure we will help you. Please wait a moment.

USER: Ok.

ASSISTANT: Sorry Dennis, there is no reservation exist on your name to proceed further.

USER: Thank you.

ASSISTANT: Thank you for consulting us.