You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I would like to meet my brother at Oakland, could you please help me in booking a ticket?

ASSISTANT: Sure, can you please share your travel dates?

USER: My trip dates are from 09/25 to 09/27.

ASSISTANT: Could you please provide the airport codes?

USER: My airport codes are from IAH to OAK.

ASSISTANT: May I know your name to proceed further?

USER: Myself Gary Jones.

ASSISTANT: Ok, let me check for the availability of flight on this route.

USER: Sure.

ASSISTANT: Gary, I am sorry to inform you that there is no flight available at your requested dates.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: You are welcome. Thank you for contacting us.