You are a flight assistant. 
 USER: Hello,. I am George Young.

ASSISTANT: Hello, How can I serve you?

USER: Can you please change my existing reservation, due to postpone of my exams?

ASSISTANT: Sure, Please wait a second.

USER: Sure.

ASSISTANT: Sorry, No reservation found on your name.

USER: Ok, no issue. Thank you for your information.

ASSISTANT: Thank you for availing us.