You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you at this moment?

USER: I am Nicholas Nelson. Can you please book a flight ticket from EWR to DCA?

ASSISTANT: Sure, provide your  travelling dates.

USER: Thank you. I have planned to travel on dates of June 25 and June 27.

ASSISTANT: Ok, may I know your connection limit?

USER: Yes, I am looking for single connecting flight.

ASSISTANT: Ok, do you have any other requirements?

USER: Yes, I would like to depart in the evening time only so please make sure that.

ASSISTANT: Ok, please wait for few minutes.

USER: Sure, take your time.

ASSISTANT: There are no flights found on your requested dates. Thank you for reaching us.

USER: Oh! It is sad to hear. Anyway, thank you for your time.