You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I am planning to go for DCA from OAK. Can you please help me out?

ASSISTANT: Sure, I will help you. May I know your planned journey dates?

USER: My planned trip dates are Jan 29 and Jan 31.

ASSISTANT: Your good name please?

USER: Myself Joseph Nelson.

ASSISTANT: Let me know your connection  limit.

USER: I want single connection flight.

ASSISTANT: Which class will you prefer for your journey?

USER: I prefer economy class ticket.

ASSISTANT: Do you have any other requirements?

USER: I need my depart and return ticket at afternoon time.

ASSISTANT: Please, wait a minute.

USER: Ok, sure.

ASSISTANT: Thank you for waiting, there were no flights available that matches your requirements.

USER: Thank you for your information.

ASSISTANT: Thank you for approaching us.