You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you?

USER: I want to cancel my reservation, due to an emergency.

ASSISTANT: Sure, can I know your name?

USER: My name is Charles Brown.

ASSISTANT: Please wait for a moment. Sorry Brown, there is no reservation found on your name.

USER: That's ok, thank  you for checking.

ASSISTANT: Welcome, thank you for reaching us.

USER: Welcome.