You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you at this moment?

USER: I am Brian Lewis, can you help me with changing my reservation to new travel dates?

ASSISTANT: Sure, I am happy to help you with that.

USER: Thanks.

ASSISTANT: Please wait a moment to check your reservation status.

USER: Sure, take your own time.

ASSISTANT: Sorry Brian Lewis, no reservation has found under your name to change.

USER: It's ok, thanks for your information.

ASSISTANT: Thank you for choosing us, have a good day.