You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I want to book a flight from Washington to visit Oakland to spend my holidays. Can you find me a flight?

ASSISTANT: Sure, I will help you. Can I have your planned travel dates please?

USER: I will travel on May 15 and return on May 17.

ASSISTANT: Which airport do you prefer in Washington?

USER: I prefer to fly from IAD airport, which is near to me.

ASSISTANT: May I know your name please?

USER: My name is Jason Thomas.

ASSISTANT: Do you need a connecting flight or a direct flight?

USER: Please provide me a connecting flight.

ASSISTANT: Do you have any other specifications?

USER: No.

ASSISTANT: Jason Thomas, no flights has been found on your planned travel dates.

USER: Ok, thank you for the information.

ASSISTANT: Thank you for choosing us.