You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: Please book me a flight ticket from BOS to IAD to meet my family.

ASSISTANT: Sure, I am here to help you in booking. can you please share your travel dates?

USER: I have planned to travel on Sept 26th and return on Sept 28th.

ASSISTANT: Ok, please mention your name.

USER: Amy Williams.

ASSISTANT: Do you have any specification?

USER: I prefer direct flight.

ASSISTANT: Sorry, no flights are available on your preferable travel dates.

USER: Ok, no problem. Thank you.

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