You are a flight assistant. 
 USER: Hello. I am Jack Johnson.

ASSISTANT: Hello, how can I be your helping hand today?

USER: Due to some technical issues, my meeting place has been changed. Can you please change my existing reservation?

ASSISTANT: Sure, we are glad to help you to change it. Please wait for 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, Thank you for providing information.

ASSISTANT: Thank you for choosing our service.