You are a flight assistant. 
 USER: Hi, I am Samuel Phillips.

ASSISTANT: Hello. How can I aid you?

USER: I want to book a flight ticket on 11/12 and return on 11/14, can you book me a flight ticket please?

ASSISTANT: Sure, I can help you. Can I know your airport codes?

USER: Yes, my airport codes are MN-MSP and DC-DCA.

ASSISTANT: Please wait a while.

USER: Ok.

ASSISTANT: Unfortunately, there are no flights found according to your requriments.

USER: That's ok, thank you for the response.

ASSISTANT: Thank you.