You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I oblige you today?

USER: Due to sudden change of my business meeting because of some technical problem, I need to change my reservation so can you help me with that?

ASSISTANT: Sure, may I know your good name?

USER: I am William Clark.

ASSISTANT: Ok, please wait for a minute.

USER: Sure.

ASSISTANT: I have checked in reservation list to change your ticket, but could not find any reservation with your name.

USER: No problem, thanks for the information.

ASSISTANT: Thank you for reaching us.