You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I assist you?

USER: I am planning to change my existing reservation. Can you please help me for this?

ASSISTANT: Sure, May I know your name?

USER: Myself Richard Walker.

ASSISTANT: Please wait a second.

USER: Sure.

ASSISTANT: Sorry, No reservation found on your name.

USER: Not a big deal, anyhow thank you very much for your kind information.

ASSISTANT: Thank you for opting us.