You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Barbara Baker.

ASSISTANT: How may I aid you?

USER: I need a flight ticket booking from DEN to DCA to attend a seminar, can you please help me in booking?

ASSISTANT: Sure, I am happy to aid you with the flight ticket booking. Can you please provide me your travel dates?

USER: Thank you and my planned dates are May 14th and recur back on May 16th.

ASSISTANT: Ok, please tell me your airlines preference.

USER: I can travel in any flight.

ASSISTANT: Ok, please give me a minute.

USER: Sure and I would like to depart on afternoon time.

ASSISTANT: Sorry to inform you that, I have not found any flight which is departing in the afternoon time on the dates you have given.

USER: Sad to hear that from your side but anyway, thank you for your information.

ASSISTANT: You are most welcome. Thank you for reaching us.