You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, How can I provide assistance to you?

USER: I want to change an existing reservation due to my meeting got preponed. Can you change my reservation which is in the name of Samantha Davis?

ASSISTANT: Sure, I am blissful to help you. 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, not a problem at all. Thank you for being my helping hand.

ASSISTANT: Thank you for availing us, Have a wonderful day.