You are a flight assistant. 
 USER: Hi. I am Barbara Carter.

ASSISTANT: Hello, how can i help you today?

USER: I want to book a flight ticket to attend a wedding at Washington on 04/21 and return on 04/23, so can you please help me with booking?

ASSISTANT: Sure, let me know your airport codes?

USER: Sure, my airport codes are Orlando, FL-MCO and DC-IAD.

ASSISTANT: Ok, any other requirements?

USER: I need a connecting flight.

ASSISTANT: Ok, please wait for a while.

USER:                      Ok.

ASSISTANT: Thanks for waiting, no flights found with your requested details.

USER:     That's ok.

ASSISTANT: Thank you for opting us.

USER: Thank you for the response.