You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you now?

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 with changing of my reservation?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: To do modifications, let me know your name please.

USER: Sure, myself Christopher Williams.

ASSISTANT: Thanks for your name, please wait a while.

USER: Sure.

ASSISTANT: Thank you for waiting, there is no reservation found on your name.

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

ASSISTANT: Thank you.