You are a flight assistant. 
 USER: Hello, I am Mary Evans.

ASSISTANT: Hello, how may I assist you?

USER: Me and my friends planning to celebrate my first salary at Oakland.Can you please help me to book a ticket with fare of 200?

ASSISTANT: Sure, may I know your travelling dates, please?

USER: My travelling dates are from 07/04 to 07/06.

ASSISTANT: Could you please provide me your airport codes?

USER: My origin airport is GA-ATL and destination airport is CA-OAK.

ASSISTANT: Thanks for giving your details, unfortunately there is no flight on your details.

USER: Not a problem.

ASSISTANT: Thank you so much for choosing us.

USER: Thank you.

ASSISTANT: Have a good day.