You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help 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 in changing my reservation?

ASSISTANT: Can I know your name?

USER: Sure, myself Timothy Evans.

ASSISTANT: Sorry, no reservation found by your name.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you.