You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you today?

USER: Can you please help me to book flight ticket from ATL to DCA?

ASSISTANT: Sure, will you mention your travelling dates please?

USER: My trip dates are Mar 30 and Apr 1.

ASSISTANT: Do you have any preferences about flight connections?

USER: I prefer a connecting flight which return in the evening.

ASSISTANT: Do you have any preferences about class?

USER: I am comfortable with any class.

ASSISTANT: Please mention your name.

USER: I am Eric Harris.

ASSISTANT: There is no flights found under your preferable details.

USER: Not a problem, thank you.

ASSISTANT: Welcome, have a great day.