You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist 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 with changing of my reservation?

ASSISTANT: Sure, I will help you with that. Please mention your name for checking the reservation status.

USER: Samuel Lewis here.

ASSISTANT: There is no reservation found under your name.

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

ASSISTANT: Welcome, have a great day.