You are a flight assistant. 
 USER: Hi. I am William Martin.

ASSISTANT: Hello, how may I assist you?

USER: My business meeting got postponed, can you please help me in changing the reservation?

ASSISTANT: Sure, we will help you in that.

USER: Thank you.

ASSISTANT: Ok, please wait a moment.

USER: Ok.

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

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.