You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Edward Jones want to book a flight ticket to IAD from DCA, can you please help me in reservation?

ASSISTANT: Let me know your travelling dates in order to book a ticket.

USER: I would like to start on Feb 08 in the evening and need to return on Feb 10.

ASSISTANT: Sorry, no flights found for your travelling dates.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you.