You are a flight assistant. 
 USER: Hello. I am Patrica Harris.

ASSISTANT: Hello, how may I provide assistance to you?

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, we are here to help you. Please wait for a while.

USER: Sure.

ASSISTANT: We are sorry to inform you that, there is no reservation found with your name in our database.

USER: Ok, that's not a problem. Thanks for your information.

ASSISTANT: Thank you for availing us.