You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: I need to travel Oakland, can you please reserve flight ticket from IAD and OAK?

ASSISTANT: Sure, may I know your planned trip dates?

USER: My travelling dates are Jan,24 and Jan,26.

ASSISTANT: Do you have any connection limit?

USER: Yes, I prefer connecting flight, that's it.

ASSISTANT: Please forward your name.

USER: Myself Melissa Phillips.

ASSISTANT: Do you have any other specifications?

USER: No.

ASSISTANT: sorry to inform you that, there are no flights found on your specified trip dates.

USER: Oh! Sad to hear that. Anyway, I will find another alternative to complete my journey. Thank you for the information.

ASSISTANT: Thank you for availing us.