You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Joseph Lewis here.

ASSISTANT: How may I assist you at this moment?

USER: Can you please book a flight ticket from ATL to LAS?

ASSISTANT: Sure, I am gleeful to help you. Can you please provide your preferable planned dates of travelling?

USER: Sure, I need to travel on dates of 04/09 and 04/11.

ASSISTANT: Please wait a moment to check the best flights available in your route.

USER: Sure, take your time.

ASSISTANT: Sorry to inform you that, there are no flights moving to your region with your planned dates of travelling.

USER: Oh! It is sad to hear.

ASSISTANT: Thank you for approaching us, have a great day.

USER: Anyway, thank you for your time.

ASSISTANT: Most welcome.