You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how best I can aid you today?

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, I am here to help you to change your existing reservation. Can I have your good name please?

USER: Thank you and myself James Smith.

ASSISTANT: Thanks for providing your name, please wait for a couple of minutes.

USER: Sure, take your time.

ASSISTANT: Sorry to inform you that, there was no reservation found on your name to change your reservation.

USER: It's ok, thank you for your help.

ASSISTANT: Thank you for approaching our service.