You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you out?

USER: I would like to book a flight ticket from BOS, can you please assist me in booking a flight ticket to DEN?

ASSISTANT: Sure, I will help you in booking the ticket. May I know your travelling dates please?

USER: My travelling dates are Sept 16th and Sept 18th.

ASSISTANT: Can I know your name please?

USER: Angela Perez.

ASSISTANT: Do you need any specifications?

USER: The depart time should be morning.

ASSISTANT: Sorry, there are no flights found.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.