You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you now?

USER: I am Robert Nelson. Due to some entrepreneurship meeting, I am going to change my existing reservation. Can you please help me in changing the reservation?

ASSISTANT: Ok, may I know your name to check with your booking status? Please be on hold for a while.

USER: Sure.

ASSISTANT: Robert Nelson, there is no reservation found by your name.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for reaching us, have a nice day.