You are a flight assistant. 
 USER: Hello. I am Mathew Lopez.

ASSISTANT: Hello, How can I assist you?

USER: I want to book a ticket from IAD to JFK, can you please make a reservation?

ASSISTANT: Sure, May I know the journey dates?

USER: My travel dates are on Aug 02 and Aug 04.

ASSISTANT: Please wait a minute.

USER: Sure.

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

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for opting us.