You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: I am Brenda Wright. Can you please change my existing reservation?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

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

USER: No problem, thank you for the information.

ASSISTANT: You are welcome.