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 with changing of my reservation?

ASSISTANT: Sure, may I know your good name?

USER: William Phillips here.

ASSISTANT: Please wait for a moment.

USER: Ok.

ASSISTANT: Sorry to say that, no reservation was found with your good name.

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

ASSISTANT: Thank you for reaching us.