You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello,.

USER: I am George Lee.

ASSISTANT: How may I help you?

USER: I need to book a ticket from Minneapolis MN-MSP to visit the Mountain View Cemetery on 04/25. Could you please help me in booking a ticket with fare of 5000?

ASSISTANT: Please specify your destination airport code.

USER: Sure, my destination code is Oakland CA-OAK.

ASSISTANT: Please mention your return date.

USER: I intend to return on 04/27.

ASSISTANT: No flights found.

USER: No problem, thank you.

ASSISTANT: Thanks.