You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: Please help me to book a flight from IAD to JFK.

ASSISTANT: Sure, can you share me your trip dates?

USER: Sure, I want to travel on Apr 19 and need to return on Apr 21.

ASSISTANT: Do you have any specifications?

USER: I need a connecting flight.

ASSISTANT: May I know your good name?

USER: I am Anna Adams.

ASSISTANT: Sorry, no flights are available in this route as per your requested dates.

USER: Ok, no problem. Thank you for checking.

ASSISTANT: Thank you for reaching us.