Hello.
Hello, how may I help you?
 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?
Sure, can I know your name please?
Myself Sarah Lee.
Sorry Sarah Lee, there is no active reservation found with your name in our records.
That's fine, thank you for checking.
Most welcome.