You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you today?

USER: I need to change my existing reservation, Can you please help me with that?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT:  I need some basic information to check your ticket details, can you please tell me your full name?

USER: Paul Adams here.

ASSISTANT: Ok, please wait a minute I will get back to you with the present status.

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, no problem. Thanks for your information.

ASSISTANT: Thank you for approaching us.