You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Barbara Nelson here.

ASSISTANT: How can I assist you Nelson?

USER: I would like to attend a business meeting at Boston, could you please help me in booking a ticket?

ASSISTANT: Sure, I can help you with that. May I know your planned travel dates please?

USER: My planned travel dates are 01/26 and 01/28.

ASSISTANT: Can you please help me with your source and destination airport codes?

USER: My source airport code is LAS and my destination airport code is BOS.

ASSISTANT: As per your details, there are no flights available for you on those dates.

USER: Ok, I will choose another means of transport. Anyways thank you for your information.

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