You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: I am Nancy Garcia. I want to book a ticket from EWR to DCA. Could you help me?

ASSISTANT: Sure, I can aid you in booking flight ticket. Can you please mention your travel dates for booking flight ticket?

USER: My preferable dates are from 07/06 to 07/08.

ASSISTANT: Please hold on a moment, I will check flight availability in this route.

USER: Ok.

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

USER: That's ok, no problem. Thank you for helping me.

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