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

ASSISTANT: Hello, how can I aid you today?

USER: I would like to book a flight ticket to Oakland, CA - OAK. Can you help me in this?

ASSISTANT: Sure, please share your journey dates.

USER: my trip dates are 11/14 - 11/16.

ASSISTANT: Ok, may I know your source point?

USER: I want to fly from Denver, CO  -DEN.

ASSISTANT: Ok, please wait for a while.

USER: Ok.

ASSISTANT: Sorry to say that, there were no flights found on that route.

USER: It's ok, not a problem. Thank you for your information.

ASSISTANT: Thank you for choosing us.