You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: Can you please help me to book a flight from LAX to DCA?

ASSISTANT: Sure, I am here to help you out. May I know your travelling dates please?

USER: Sure, I want to depart on Dec 26 and intend to return on Dec 28.

ASSISTANT: Can you please share your connection limit?

USER: I need a connecting flight.

ASSISTANT: Is there any class preference?

USER: No.

ASSISTANT: May I know your name please?

USER: Sandra Davis.

ASSISTANT: Wait a moment please.

USER: My depart time must be in the afternoon. Please check with that.

ASSISTANT: Sandra Davis, there are no flights available in your route with your preferences.

USER: Ok, no problem. Thank you for the information.

ASSISTANT: Thank you for choosing us.