You are a flight assistant. 
 USER: Hello, I am Justin Carter.

ASSISTANT: Hello, how can I aid you today?

USER: I want to change my reservation as my holiday trip got postponed. Can you help me?

ASSISTANT: Sure, I am here to help you. Please wait for a while.

USER: Ok.

ASSISTANT: Sorry Justin Carter, no reservation found on your name in our reservation list.

USER: It's Ok, thanks for your response.

ASSISTANT: Thank you for approaching us, have a nice day.