You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: Can you please book a direct flight to Oakland?

ASSISTANT: Sure, I will help you out. May I know your travelling dates please?

USER: My travel dates are 11/04 and 11/06.

ASSISTANT: Can I know your airport codes too?

USER: My airport codes are from ORD to OAK.

ASSISTANT: May I know your name please?

USER: Myself Brian Wright.

ASSISTANT: Ok, please wait a moment.

USER: Ok.

ASSISTANT: Sorry, there are no flights found.

USER: No problem, thanks for checking.

ASSISTANT: Thank you for reaching us.