You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I guide you now?

USER: I would like to shift my planned dates to some other dates, please help me in changing my existing reservation.

ASSISTANT: Sure, I will help you with changing.

USER: Thank you.

ASSISTANT: Can I know your name for checking your previous flight ticket booking in our data base?

USER: My name is Jeffrey Hall.

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 issues. Thank you for your information.

ASSISTANT: You are most welcome and thank you for utilising our service.