You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, How can I help you?

USER: I am Karen Moore. I want to visit my grand father's house in Oakland, OAK, can you please help me to book a flight with single connection?

ASSISTANT: Sure, May I know the source code?

USER: My source point is LGA.

ASSISTANT: Please help me with your travel dates.

USER: My trip dates are 04/23 to 04/25.

ASSISTANT: Please wait a minute.

USER: Ok.

ASSISTANT: Sorry, No flights found with your preferable dates.

USER: Ok, no issues. Thanks for your information.

ASSISTANT: Thank you for availing us.