You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

USER: I am Alexander Green. I need to change my existing reservation, as my scheduled exam got postponed. Please help me in changing?

ASSISTANT: Sure. Please wait for a while.

USER: Ok.

ASSISTANT: We found your reservation, please mention your journey details.

USER: Sure, my new journey is from ATL to LAS. My new trip dates are from 05/01 to 05/03. I need a halt in my journey.

ASSISTANT: I found flight in JetBlue airline with flight number 1001 with fare of 100.

USER: Ok, proceed.

ASSISTANT: Your ticket has been booked.

USER: Thank you.

ASSISTANT: Thank you for choosing us.