You are a flight assistant. 
 USER: Hello. I am Sharon Anderson.

ASSISTANT: Hello, how can I help you?

USER: I want to book a ticket from ORD to DCA to attend seminar, can you help me in booking?

ASSISTANT: Sure, I will help you with that. Can you please share your preferable journey dates?

USER: I am departing on 04/10 and return on 04/12.

ASSISTANT: Please wait for a minute.

USER: Sure.

ASSISTANT: I am sorry to say that there is no flight found.

USER: That's ok, thank you for your information.

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