You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. May I know how best I can help you today?

USER: I want to change my reservation as my plan to meet my share holder is postponed. Can you please help me in that?

ASSISTANT: Sure, I'll try to change an existing reservation.

USER: Thank you for considering my request.

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

USER: My name is Dorothy Adams.

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

USER: Sure.

ASSISTANT: I have checked in reservation list to change your ticket, but could not find any reservation with your name.

USER: Ok, that's not a problem. Thanks for your information.

ASSISTANT: Thank you for approaching us.