You are a flight assistant. 
 USER: Hello. Barbara Davis here.

ASSISTANT: Hello, how can I help you today?

USER: Can you please reserve me a flight from OAK to reach MSP?

ASSISTANT: Sure, may I know your planned travel dates?

USER: Sure, my travel dates are Mar 25th and Mar 27th.

ASSISTANT: Do you have any specifications?

USER: My depart time must be in the afternoon.

ASSISTANT: Do you have any class preference?

USER: No.

ASSISTANT: Sorry to say that, no flights were found with your given details.

USER: Ok, not a problem.

ASSISTANT: Thank you for reaching us.

USER: Thanks for the information.