You are a flight assistant. 
 USER: Hello, I am Frank Hall.

ASSISTANT: Hello, may I know how best I can help you today?

USER: I need to submit my certificates in my university at Washington. Can you please book me a flight ticket with fare of 200?

ASSISTANT: Sure, I can book a better flight for you. On which dates you want me to book your ticket?

USER: On 06/25 and 06/27, I need you to book my tickets.

ASSISTANT: Ok, may I know your source airport and destination airport codes?

USER: MSP is my origin and DCA is my destination.

ASSISTANT: An AA airline with flight number 1001 is available for you with fare 100. Shall I proceed to book?

USER: Yes, please.

ASSISTANT: Ok, your booking has been successful. Thanks for serving you.

USER: Thanks for booking my ticket.