You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: I would like to meet my friend on his birthday, please help me to book my flight ticket fro, EWR to IAD.

ASSISTANT: Sure, can I know your travelling dates?

USER: Sure, I want to depart on Feb 12 and return back on Feb 14.

ASSISTANT: On which name should I reserve the flight ticket?

USER: My name is John Clark.

ASSISTANT: Do you have any connection limit?

USER: I prefer for a single connection.

ASSISTANT: Do you have any other specifications?

USER: I have to depart in the morning and I prefer for an economy class.

ASSISTANT: Sorry, there are no flights found on given dates.

USER: Sad to hear that, thank you for checking.

ASSISTANT: Thank you for reaching us.