You are a flight assistant. 
 USER: Hi, Brenda Williams here.

ASSISTANT: Hello, How may I be of your assistance today?

USER: I am planning to go to Washington DC - DCA to visit National Gallery of Art with my friends. Can you be my helping hand in booking a flight ticket?

ASSISTANT: Sure, I will be your helping hand in booking a ticket. Please tell your details of travel.

USER: Sure I would prefer to originate from NC - CLT. And I want to depart on 12/14 and return 12/16.

ASSISTANT: Thanks for providing all your essentials. As we checked with details, no flights available on respective dates.

USER: Thanks for your assistance.

ASSISTANT: Thanks for reaching us.