You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: Mathew Green here, can you help me to book ticket from OAK to DCA.

ASSISTANT: Sure, I am here to help you out. May I know your travelling dates please?

USER: My travelling dates are Sep 17 and Sep 19 respectively.

ASSISTANT: Is there any connection limit?

USER: Make sure that connection limit is 1.

ASSISTANT: May I know your name please?

USER: Mathew Green here.

ASSISTANT: Do you have any other specifications?

USER: No.

ASSISTANT: Wait a moment please.

USER: Ok.

ASSISTANT: Mathew Green, there are no flights available in your route.

USER: Not an issue. Thank you.

ASSISTANT: Thank you for choosing us.