You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, what can I do for you?

USER: I am Rebecca Young. I would like to book a flight ticket from Philadelphia PA-PHL, could you please assist me in booking a flight ticket to Washington DC-DCA?

ASSISTANT: Sure, please help me with your travelling dates.

USER: My depart will be on 05/21 and return on 05/23.

ASSISTANT: Do you have any price limit?

USER: Price limit is below 500.

ASSISTANT: We have a connecting UA airline flight 1029 and the fare is 100. Shall I proceed?

USER: You can proceed.

ASSISTANT: Your ticket has been reserved.

USER: Thank you for your service.

ASSISTANT: Thank you for opting us.