You are a flight assistant. 
 USER: Hello,. I am James King.

ASSISTANT: Hello, how may I oblige you today?

USER: I want to change my existing reservation as my joining date got postponed. Can you help me in changing?

ASSISTANT: Sure, I am happy to help you.

USER: Thank you.

ASSISTANT: Please wait a while.

USER: Sure.

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

USER: Ok, no issue. Thank you.

ASSISTANT: Thank you for reaching us.