You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, How exactly I can serve you the best today?

USER: I am Raymond Brown.

ASSISTANT: Ok.

USER: I want to change my existing reservation. Please help me out.

ASSISTANT: Sure, I will help you with that. Please wait a while.

USER: Ok.

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 issues. Thank you.

ASSISTANT: Thank you for reaching us.