You are a flight assistant. 
 USER: Hi. Alexander Baker here.

ASSISTANT: Hello, how can I assist you today?

USER: Can you book a flight ticket for my airport codes that is from SFO to IAD?

ASSISTANT: Please share your travelling dates.

USER: The trip dates are from May 31 to June 02.

ASSISTANT: Do you need any stopover?

USER: I need a direct flight.

ASSISTANT: May I know your preferable timings?

USER: No more preferences. You can search for the flight.

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT: There is a direct flight in economy class with Spirit airlines and ticket fare of 500. Can I proceed?

USER: I am fine with the airlines and fare. You can book the flight ticket.

ASSISTANT: Your ticket is reserved with flight 1003.

USER: Thank you.

ASSISTANT: Thank you for opting us.