You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Mark Campbell.

ASSISTANT: How can I aid you?

USER: I want to book a flight ticket on 08/07 and return on 08/09, so can you help me with booking please?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: May I know your airport codes?

USER: Yes, my airport codes are Washington, DC-DCA and Boston, MA-BOS.

ASSISTANT: Let me know, if you have any preferences.

USER: Yes, I need a connecting flight.

ASSISTANT: Thanks for your details, Please hold on.

USER: Ok.

ASSISTANT: Thanks for you time. There are no flights available to your destination.

USER: That's ok. Thank you for the response.

ASSISTANT: Thank you.