You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I assist you today?

USER: Can you please help me in changing my existing reservation?

ASSISTANT: Sure, could you please share your name to proceed further?

USER: Myself, Nicholas Lee.

ASSISTANT: Ok, please wait a moment.

USER: Ok.

ASSISTANT: Thank you for your time, unfortunately no reservation found on your name.

USER: Ok, no issues. Thank you for checking.

ASSISTANT: Thank you for reaching us.