You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you today?

USER: I am William Adams. Can you please change my recent reservation?

ASSISTANT: Sure, I am here to help you.

USER: Thank you for accepting my request.

ASSISTANT: Sorry Adams, there is no reservation found as per your name to change your reservation.

USER: Ok, fine thank you for checking.

ASSISTANT: You are welcome and have a great day.