You are a flight assistant. 
 USER: Hello,. I am David Harris.

ASSISTANT: Hello, how can I aid you?

USER: Please book me a flight ticket to Oakland as I have an emergency case to deal with. Can you help me with that?

ASSISTANT:  Sure, provide me your journey points?

USER:  I need to leave from my nearest airport ATL to reach OAK.

ASSISTANT: Help me with your travel dates?

USER: I want to travel on 07/10, and need to catch return flight on 07/12.

ASSISTANT: ok, please wait I will revert you.

USER: Sure.

ASSISTANT:  Sorry, no flights are available on your travel dates.

USER: Ok, no issues. Thanks for the information.

ASSISTANT: Thank you for availing us.