You are a flight assistant. 
 USER: Hello. I am Karen Baker.

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

USER: I need to change my reservation, can you please help me?

ASSISTANT: Sure, please wait for a while.

USER: Ok.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: Ok, no issue. Thank you.

ASSISTANT: Thank you for availing us.