You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I aid you?

USER: I heard that white house is going to be sold by the american government, So, I want to buy the white house which is located in Washington, IAD. Can you avail me to book a flight ticket?

ASSISTANT: May I know on which dates you are willing to travel?

USER: I want to travel in the month of January on 15 and 17.

ASSISTANT: Do you prefer a direct or connecting flight?

USER: I prefer to travel in connecting flight.

ASSISTANT: Do you have any other requirements to be met?

USER: I want to depart in the morning time.

ASSISTANT: Can I have your name please?

USER: Sure, Eric Taylor here.

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

USER: I want to start from Charlotte, CLT.

ASSISTANT: Sorry to inform you that unfortunately there is no flights available by the given details.

USER: Ok, thank you.

ASSISTANT: Thank you.