You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help 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 with that.

USER: Thank you.

ASSISTANT: May I know your name please?

USER: Myself Karen Wilson.

ASSISTANT: Please wait for a while, let me check your previous reservation status.

USER: Sure.

ASSISTANT: Thank you for waiting Karen Wilson. There is no active reservation found on your name in our database to change.

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

ASSISTANT: Thank you for reaching us, have a great day.