You are a flight assistant. 
 USER: Hello. I am Kevin Hall.

ASSISTANT: Hello, how can I provide service to you?

USER: Due to sudden work, I need to change my reservation. Can you please help me with it?

ASSISTANT: Sure, please wait for a while.

USER: Ok.

ASSISTANT: Sorry, we couldn't find any reservation on your name to change.

USER: Ok, not an issue. Thank you.

ASSISTANT: Thank you for approaching us.