You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: I want to change my reservation, can you help me?

ASSISTANT: Sure, I can help you. Please give me a moment to check your ticket status. May I know your name?

USER: I am Nicholas Lee.

ASSISTANT: Sorry Nicholas Lee, no reservation is available by your name.

USER: No problem, thanks for checking.

ASSISTANT: Thank you for reaching us.