You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Due to inconvenience of my work, I want to change my reservation. Can you please help me for that?

ASSISTANT: Sure, I will help you and may I know on whose name the previous ticket is booked?

USER: My name is Samuel King.

ASSISTANT: Please give me some time to check it.

USER: Ok, I will wait.

ASSISTANT: I regret to inform you that, I am unable to find your ticket booking done on your name in our data base to change it.

USER: Anyway, thanks for the information.

ASSISTANT: You are most welcome.