You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: Can you please help me to change my reservation?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Can I know your name please to proceed further?

USER: My name is Benjamin White.

ASSISTANT: Sorry to inform you that there is no active reservation on your given name.

USER: Ok, not a problem. Thank you.

ASSISTANT: Thanks for reaching us, have a nice day.