You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you today?

USER: I want to change my existing reservation, which is done recently. Can you please help me out?

ASSISTANT: Sure, I will help you with that. Can I know your name to check your previous reservation?

USER: Thank you for considering my request. My name is Edward Hill.

ASSISTANT: Please be on hold to check.

USER: Sure, I will wait.

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. Thank you for your service.

ASSISTANT: Thank you for using our services, hope you have a great day.