You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Robert Perez.

ASSISTANT: How may I assist you?

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

ASSISTANT: Sure, please wait for a moment to check your details. Sorry to say, no reservation found on your name.

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

ASSISTANT: Thank you for choosing us, have a nice day.

USER: Welcome.