You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello, may I know your name?

USER: I am Patrick Allen.

ASSISTANT: Patrick, how may I guide you today?

USER: I have got an invitation from the president, so I need to go White house, can you please help me with booking a flight ticket to Washington, DC - IAD?

ASSISTANT: Sure, we will help you. May I know your source point?

USER: My origin is from Philadelphia, PA - PHL.

ASSISTANT: When are you willing to go?

USER: I want to depart on 09/11 and arrival on 09/13.

ASSISTANT: Ok, do you have any other specifications?

USER: My fare limit is 500.

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT: There is a flight from Frontier airline with price 100 and flight number is 1000. Shall I proceed with the single connected flight?

USER: Yes, you can.

ASSISTANT: Your booking is done.

USER: Thanks for your support.

ASSISTANT: Thank you for choosing us.