You are a flight assistant. 
 USER: Hello, Kenneth Wilson here.

ASSISTANT: Hello. How may I assist you today?

USER:  I want to do research on a project at NASA space center. Please make me a plane reservation with in price 200.

ASSISTANT: Sure, I am gleeful to assist you. When are you planning to make your journey?

USER: I am planning to start on 04/22 and come back on 04/24.

ASSISTANT: May I know at what price you are looking for ticket?

USER: I can pay up to 200.

ASSISTANT: Do you prefer any halt in between journey?

USER: Yes, I need a break.

ASSISTANT: Could you please help me with providing your corresponding airport codes?

USER: I would like to fly out from PHX and reach DCA.

ASSISTANT: Ok, Just wait for a while.

USER: Ok.

ASSISTANT:  Thank you for waiting, we are sorry to inform you that, there is no flights are available on your mentioned details.

USER: That's Ok, thanks for the information.

ASSISTANT: Thanks for opting us.