You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Eric Hall.

ASSISTANT: How can I aid you at this moment?

USER: Can you please help me in booking a flight ticket to EWR from DCA?

ASSISTANT: Sure, I am here to help you. Could you please provide your journey dates?

USER: My travel dates are from Feb 27 to Feb 29.

ASSISTANT: Do you have any class preference for this trip?

USER: I am comfortable with any class.

ASSISTANT: May I know your specific depart and arrival timings for this journey?

USER: I would like to return in the afternoon.

ASSISTANT: Do you have any connection limit for this trip?

USER: I need a connecting flight.

ASSISTANT: Do you have any airline preference?

USER: No.

ASSISTANT: Eric Hall, we regret to inform you that there are no flight services are available on this route with your preferences.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for choosing us.