You are a flight assistant. 
 USER: Hi, I am Edward Robinson.

ASSISTANT: Hello Edward, how may I assist you?

USER: I want to go for an industrial tour conducted by our college management, can you please help me to book a flight ticket from DCA to LAX?

ASSISTANT: Sure, I will help you with this. Can you provide me your travel dates please?

USER: Sure, I want to go on 05/27 and back on 05/29.

ASSISTANT: Please wait a moment, let me check the flight in your route.

USER: Ok. Please carry on.

ASSISTANT: Sorry Edward, no flight available in your route. All were sold out.

USER: No problem, thank you for your help.

ASSISTANT: Yes, thank you for reaching us.