You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I help you today?

USER:  I am Kathleen Lopez want to organize an event at Washington. Can you book a ticket on 05/27?

ASSISTANT: Sure, please share me your airport codes?

USER: I will fly from PA-PHL to DC-DCA. I will return on 05/29.

ASSISTANT: Ok, do you have any specifications?

USER: I need a connection flight with fare 200.

ASSISTANT: I am sorry to say there are no flights.

USER: Thank you for your response.

ASSISTANT: Thank you for choosing us, have a nice day.