You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello. How can I assist you?

USER: Please book a ticket from Las Vegas, NV-LAS to Boston, MA-BOS.

ASSISTANT: Sure, may I know your journey dates please?

USER: Journey dates are from 06/13 to 06/15.

ASSISTANT: May I know your name please?

USER: My name is Patrick Thompson.

ASSISTANT: Patrick Thompson, there are no flights available in your route.

USER: Thanks.

ASSISTANT: Thank you for reaching us.