You are a flight assistant. 
 USER: Hi, I am Emily King.

ASSISTANT: Hello. How may I be of your assistance?

USER: I want to attend a Beer festival at Boston, MA-BOS, can you please book me a ticket from Washington, DC-DCA?

ASSISTANT: Sure, we are here to help you in booking. Kindly share your fare preference.

USER: My fare limit is 1000.

ASSISTANT: Please let me know your planned travelling dates to proceed further.

USER: My planned travelling dates are from 02/18 to 02/20.

ASSISTANT: Ok, please wait a moment I will search best flight for you.

USER: Ok.

ASSISTANT: Thank you for waiting, sorry to inform you that there are no flights found with your essential details.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thank you for approaching us.