You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: I want to change an existing reservation, Can you please help me in that?

ASSISTANT: Sure, I am here to help you. May I know your name to proceed?

USER: My name is Angela Lewis.

ASSISTANT: Please wait for a moment.

USER: Sure.

ASSISTANT: Sorry to say, no reservation found on your name.

USER: Ok, that's not a problem. Thanks for your information.

ASSISTANT: Thank you for reaching us.