You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: My name is Patricia Thomas. I have a business meeting in Houston, can you help me for booking a flight ticket from LAS to HOU?

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

USER: My travelling dates are 08/19 and 08/21.

ASSISTANT: Sorry, no flights are available on your route.

USER: That's ok, thank you for checking.

ASSISTANT: Welcome, have a nice day.