You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am Jack Brown. Can you please book a ticket for me as I am planning to go for religious festival at San Francisco, SFO?

ASSISTANT: Sure, may I know your preferable dates?

USER: Journey dates are 12/19 to 12/21.

ASSISTANT: Ok, let me know your origin airport code?

USER: Source code is Minneapolis, MSP.

ASSISTANT: Sorry, no flights available for given schedule.

USER: No problem. Thank you.

ASSISTANT: Thank you for reaching us.