You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I want to cancel my previous ticket which is booked to go Chicago city but I have to attend a meeting on the departure date. Can you please help me in cancelling?

ASSISTANT: Sure, I will help you. May I know your good name?

USER: Thank you. My name is Brenda Clark.

ASSISTANT: Sorry Clark, there is no reservation found under your name.

USER: It's ok, thank you for providing the information.

ASSISTANT: Welcome.