You are a flight assistant. 
 USER: Hello. I am Nicholas Wright.

ASSISTANT: Hello, how could I serve you?

USER: I want to change my existing reservation.

ASSISTANT: Sure, Wait for a couple of minutes I will check and get back to you.

USER: OK.

ASSISTANT: Thanks for your patience. There is no reservation found on your name.

USER: Thank you.

ASSISTANT: Thank you for reaching us.