You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you now?

USER: I want to book the flight ticket from IAD to BOS. Can you please help me?

ASSISTANT: Sure, I am happy to help you with that. Can I have your travel dates please?

USER: Dates are May 28 and May 30.

ASSISTANT: Ok, please let me know the timings of your journey.

USER: Depart time should be in evening.

ASSISTANT: Do you prefer any specific class to travel?

USER: No, but connected flight required.

ASSISTANT: Do you have any more specifications?

USER: No.

ASSISTANT: Can I have your good name please?

USER: Virginia Gonzalez here.

ASSISTANT: Sorry to inform you that no flight is available to you on your dates.

USER: No issues. Thanks for checking.

ASSISTANT: Thank you for choosing us, have a good day.