You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

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

ASSISTANT: Sure, may I know your name please?

USER: Nicholas Evans here.

ASSISTANT: May I know your travelling dates please?

USER: My travelling dates will be on July 26 to July 28.

ASSISTANT: May I know your class preference please?

USER: I do not have any class preference.

ASSISTANT: May I know your connection limit please?

USER: I would prefer a direct flight.

ASSISTANT: Do you have any other specifications please?

USER: No.

ASSISTANT: Sorry Evans, there is no reservations found as per your travelling details.

USER: Ok, not an issue. Thank you.

ASSISTANT: You are welcome.Thank you for reaching us.