You are a flight assistant. 
 USER: Hi. I am Donald Hill.

ASSISTANT: Hello, how may I be there for you?

USER: I am planning for a round trip in Oakland, so can you please book me a direct flight?

ASSISTANT: Sure, may I know your airport code?

USER:  Yes, my airport code is CA-OAK.

ASSISTANT: When are you planning to travel?

USER: I am planning to travel on 10/02 and return on 10/04.

ASSISTANT: Ok, please wait.

USER: Ok.

ASSISTANT: Thanks for waiting, There are no flights at this moment on your required dates.

USER: That's ok. Thank you for the response.

ASSISTANT: Thank you for picking us.