You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, can I help you?

USER: Kevin White here. My music concert is postponed on next week. Can you alter my reservation?

ASSISTANT: Sure, I will check your previous reservation, please be on hold for a while. Sorry to inform you, I didn't find any reservation under your name.

USER: It's ok. Thanks for searching.

ASSISTANT: You are welcome.