You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how can I assist you?

USER: I want to celebrate my brother birthday party in Boston, MA - BOS, will you help me in booking flight ticket?

ASSISTANT: Sure, we are here to help you only. Can you please share your journey details?

USER: My origin source from Las Vegas, NV - LAS, and my journey dates from 05/27 to 05/29.

ASSISTANT: OK, please be patience.

USER: Sure.

ASSISTANT: I will check with airlines and revert you.

USER: Ok.

ASSISTANT: Sorry for the inconvenience caused, no flights found on your preferred dates. Thank you for connecting with us, have a nice day.

USER: Thank you, for your service.