You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: Myself Daniel Jones.

ASSISTANT: Yes, Jones.

USER: Actually, I want to postpone my wedding ceremony. So, I want to change my existing reservation.

ASSISTANT: Sure, I will help you for that.

USER: Ok.

ASSISTANT: Wait a moment. Sorry Jones, there is no reservation found on your name to change.

USER: It's ok, thank you for checking.

ASSISTANT: Thank you for choosing us.