You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Kathleen Roberts here.

ASSISTANT: How may I help you at this moment?

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 with that.

USER: Thank you for accepting my request.

ASSISTANT: Please wait for a minute Roberts.

USER: Ok, take your time.

ASSISTANT: Sorry to say that, there is no reservation found on your name in our database.

USER: Oh! I think the ticket was not booked due to server issue. Anyways, thank you for the information.

ASSISTANT: Thank you for approaching us.

USER: Welcome.