You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: I am Sarah Lopez, can you help me to book a flight ticket?

ASSISTANT: Sure, I am here to help you out. Please share me your trip dates.

USER: Ok, my travel dates are 08/12 and 08/14 respecively.

ASSISTANT: May I know your location airport codes?

USER: My origin airport code is LAS and destination code of the airport is OAK.

ASSISTANT: Sorry Lopez, there is no flight in your route.

USER: That's ok I will try next time. Thank you for helping me.

ASSISTANT: Thank you for reaching us.