You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you at this moment?

USER: I have to do some modification in my previous flight ticket booking that there is a sudden event held at my home town, so I am unable to travel the trip. Can you please help me out in changing my reservation?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: May I know your name to check your reservation status?

USER: My name is Anthony Brown.

ASSISTANT: Ok, please be on hold.

USER: Sure.

ASSISTANT: Thank you for waiting, sorry to inform you that we could not find any  reservation on your name.

USER: It's ok, thank you.

ASSISTANT: Thank you for choosing us.