You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Virginia Miller. I am planning to book a ticket from DCA to LAS. Can you please help me out?

ASSISTANT: Sure, I am happy to help you. Please let me know your travel dates.

USER: I am planning to travel on July 26 and return back on July 28.

ASSISTANT: Ok, may I know your specifications?

USER: My return time should be evening.

ASSISTANT: Ok, please be on hold for a while.

USER: I am looking for a connecting flight.

ASSISTANT: Sorry to tell you that there is no flight available as per your requirements.

USER: That's fine, thank you for your service.

ASSISTANT: You are welcome and have a nice day.