You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you today?

USER: I am looking to book a flight ticket from EWR to DCA. Can you help me for that?

ASSISTANT: Sure, can you please share your preferable journey dates?

USER: My travelling dates are Apr 27 and Apr 29.

ASSISTANT: May I know your name please?

USER: My name is Andrew Hernandez.

ASSISTANT: Do you have any other specifications?

USER: I prefer to book a single connecting flight.

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

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for reaching us.

USER: Welcome.