You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Can you please help me in booking a flight ticket from Houston, IAH to Oakland, OAK?

ASSISTANT: Sure, please share your journey dates?

USER: My journey dates are from Mar 28 to Mar 30.

ASSISTANT: Do you have any specifications?

USER: My return time is afternoon.

ASSISTANT: Is there any class preference?

USER: No.

ASSISTANT: May I know your good name?

USER: My name is Michelle Smith.

ASSISTANT: Sorry, no flights found on your given details.

USER: Ok, that's not a problem. Thanks for your information.

ASSISTANT: Thank you for choosing us.