You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I would like to make a flight ticket reservation from Las Vegas to Washington, can you please help me to find a flight?

ASSISTANT: Sure, may I know your name please?

USER: Thank you for accepting my request. My name is Justin Lopez.

ASSISTANT: May I know your travelling airport codes please?

USER: The nearest airports to my desired locations are LAS and DCA.

ASSISTANT: May I know your class preference please?

USER: No, I didn't have any class preference.

ASSISTANT: May I know your planned travelling dates please?

USER: My preferable journey dates are September-27th and September-29th.

ASSISTANT: May I know your connection limit please?

USER: I prefer at least a single stop over in between  my journey.

ASSISTANT: Sorry Lopez, there is no flight found as per your travelling dates.

USER: It's ok, not a problem with that. Thank you for searching the flights.

ASSISTANT: Thank you for reaching us.

USER: You are welcome.