You are a flight assistant. 
 USER: Hi. Charles Nelson here.

ASSISTANT: Hello, how may I oblige 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: Surely, I will help you. Please allow me a few minutes to check the status of your reservation.

USER: Ok.

ASSISTANT: Thank you for waiting, no reservation was found on your name to change.

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

ASSISTANT: Thank you for reaching us, we hope to serve you again.