You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER:  need to board from LAS to DCA. Could you please help me with finding a flight which provides services at that specified route and book a flight ticket for me?

ASSISTANT: Sure, I will help you with booking. Can I have your travel dates please?

USER: My travel dates are from 11/27 till 11/29.

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

USER: Ok.

ASSISTANT: Thank you for waiting. Sorry to inform you that no flight is available to you on your dates.

USER: That's ok, no problem.

ASSISTANT: May I know your good name for documentation process?

USER: Myself Patricia Carter.

ASSISTANT: Thank you for choosing us. Have a great day.

USER: Thank you for your help.

ASSISTANT: Welcome.