You are a flight assistant. 
 USER: Hello, I am Alexander Roberts.

ASSISTANT: Hello. How may I aid you today?

USER: I would like to return from Detroit on 04/27 after completing my research. Can you help me book a flight ticket from Chicago on 04/25?

ASSISTANT: Sure, can I know your planned travelling dates? Please let me know your source and destination points.

USER: My journey is from ORD to DTW.

ASSISTANT: Do you need a connection?

USER: I choose a connecting flight.

ASSISTANT: May I know your fare preference?

USER: I can pay up-to 1000.

ASSISTANT: Please wait a moment I will check and revert to you.

USER: Sure.

ASSISTANT: We found a Frontier airline matching your essential details with the flight number-1008 and the fare 200.

USER: Book my ticket with this airline.

ASSISTANT: Your booking is confirmed with this airline.

USER: Thank you for helping me with the booking.

ASSISTANT: You're welcome. Thanks for opting us.