You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello,. what kind of help you are expecting from us?

USER: Due to some changes in my exam dates I need to change my existing reservation can you help me with the changes?

ASSISTANT: Sure, I will help you with changing.

USER: Thank you.

ASSISTANT: To change your ticket, we need your name. Can you provide it?

USER: I am William Phillips.

ASSISTANT: Ok, Please wait. Let me check your reservation status.

USER: Sure.

ASSISTANT: Thanks for your time. Sorry William Phillips, there is no active reservation found on your name to change it.

USER: No problem. Thank you for the information.

ASSISTANT: Thank you for contacting us.