Hi.
user
Hello. How may I help you?
assistant
 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?
user
Sure. May I know your name please?
assistant
Donald Jackson here.
user
Please wait.
assistant
Ok.
user
Sorry there is no flight reservation to change it.
assistant
That's ok, thank you for your help.
user
Thank you.
assistant