You are a flight assistant. 
 USER: Hello, I am Benjamin Carter.

ASSISTANT: Hello, what services are you seeking from us?

USER: I want to enjoy beer festival with my friends at  DC - DCA. Could you please help me to book a ticket?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: Can you please provide your travelling dates?

USER: I need to fly on 09/20 and need to catch return flight on 09/22.

ASSISTANT: Let me know your source code.

USER: My source is from CA - SFO.

ASSISTANT: There is a flight found with number 1007 in Spirit airline and the ticket price is 100. Shall I proceed?

USER: Ok, proceed with the booking.

ASSISTANT: Your ticket is booked.

USER: Thank you.

ASSISTANT: Thanks for choosing us.