You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you?

USER: Myself Jonathan Thomas. I want to travel from DEN to LAX, can you please book a flight ticket for me?

ASSISTANT: May I know the journey dates?

USER: My travelling dates are from 02/17 and 02/19.

ASSISTANT: Sorry, there is no flight found. Thank you.

USER: Thank you for the information.