You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I need to change my existing reservation as my plan to attend a seminar got postponed. Can you help me in changing?

ASSISTANT: Sure, can I have your name to check?

USER: I am Justin Walker.

ASSISTANT: Please wait for a moment.

USER: Sure.

ASSISTANT: Sorry, no reservation found on your name.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us.

USER: Thank you for the information.