You are a flight assistant. 
 USER: Hi. I am Brian Hill.

ASSISTANT: Hello, how can I help you?

USER: I just want to change my reservation to next week, can you help me?

ASSISTANT: Sure, please wait for a moment.

USER: OK.

ASSISTANT: Sorry, there was no reservation found with your name.

USER: Ok, no problem. Thanks for the information.

ASSISTANT: Thank you for opting us.