You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you for the day?

USER: I need to travel BOS and LAS, can you please reserve flight ticket for my journey?

ASSISTANT: Sure, I am here to help you with that flight ticket booking. May I know your travelling dates, please?

USER: My travelling dates are Mar,21 and Mar,23.

ASSISTANT: Which class do you prefer either economy or business?

USER: I need economy class.

ASSISTANT: Do you need a direct flight or connecting flight in your journey?

USER: I need single connection for my journey.

ASSISTANT: Is there any other requirements?

USER: No.

ASSISTANT: May I know your name please?

USER: Myself Jason Thomas.

ASSISTANT: Please hold for a moment.

USER: Sure.

ASSISTANT: Sorry to tell you that, there are no flights on this route as per your travel dates.

USER: Oh! Sad to hear that. Anyway, I will find another alternative to complete my journey.

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

USER: Thank you for the information.