You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I'm Brian Walker.

ASSISTANT: How can I assist you now?

USER: My holiday trip has been postponed. So, I would like to change my reservation. Can you please help me with that?

ASSISTANT: Sure, I will help you with that. Sorry Brian, there is no reservation found on your name.

USER: Ok, no issues. Thank you for checking.

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

USER: You are welcome.