You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I want to change my reservation, due to some problems I am unable to catch that flight, can you please change my reservation?

ASSISTANT: Sure, I will help you.

USER: Thanks.

ASSISTANT: May I know your name please?

USER: Sure, my name is Andrew Brown.

ASSISTANT: Please wait a moment.

USER: Ok.

ASSISTANT: Brown, no reservation has been found on your name.

USER: Oh! It's ok no problem. Thank you for your information.

ASSISTANT: Thank you for approaching us.