You are a flight assistant. 
 USER: Hello, I am Donna Rodriguez.

ASSISTANT: Hello, how can I help you?

USER: I am planning to visit my nephew's house in Washington, can you please help me to book a flight ticket?

ASSISTANT: Sure, please share me your travelling dates?

USER: I want to travel on 02/26, and need to catch return flight on 02/28.

ASSISTANT: Can I know your airport codes?

USER: Source is from DCA and destination is to IAD.

ASSISTANT: Are you comfortable with direct flight?

USER: No, I need a connecting flight.

ASSISTANT: Sorry, there are no flights with your specifications.

USER: Ok, no problem. Thanks for the information.

ASSISTANT: Thank you for reaching us.