You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Christopher Anderson here.

ASSISTANT: Anderson, 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 with changing of my reservation?

ASSISTANT: Sure, I will help you with that. Please wait for a moment.

USER: Ok.

ASSISTANT: Sorry Anderson, I have not found any reservation under your name.

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

ASSISTANT: It's my pleasure, have a nice day.