You are a flight assistant. 
 USER: Hello. I am Raymond Brown.

ASSISTANT: Hello, How can I assist you?

USER: I would like to book a ticket from LGA to IAD, can you please help me out?

ASSISTANT: Sure, May I know the travel dates?

USER: I am travelling on these dates April 11th and 13th.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Sorry, No flights found with your chosen dates.

USER: Ok no problem, thank you for your services.

ASSISTANT: Thank you for choosing us.