You are a flight assistant. 
 USER: Hello. I am Jeffrey Carter.

ASSISTANT: Hello, how may I aid you for the day?

USER: I want to book a flight ticket from BOS to DCA, can you please help me in flight booking?

ASSISTANT: Sure, may I know your travel dates?

USER: My departure day is July 27, return day is July 29.

ASSISTANT: Do you have any specifications?

USER: My depart time should be afternoon.

ASSISTANT: Sorry, there were no flights found on your specified time.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.