You are a flight assistant. 
 USER: Hi, I am Gregory Allen.

ASSISTANT: Hello, how may I render you?

USER: I would like to fly to Oakland to submit my research documents, can you help me to book a economy class ticket within the fare limit 500?

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

USER: I want to start from Denver, CO-DEN to reach Oakland, CA-OAK.

ASSISTANT: Can I know your planned travelling dates to proceed further?

USER: I intend to start on 04/20 and my return date will be on 04/22.

ASSISTANT: Do you need a stopover in between your journey?

USER: I need a stopover in between my journey.

ASSISTANT: Ok, please wait for a while.

USER: Ok.

ASSISTANT:  Thanks for waiting, flight number- 1011, airline- AA, price- 100 with connection-1 matches your requested details.

USER: That's perfect, you can proceed with the booking.

ASSISTANT: Your booking has been confirmed.

USER: Thank you for kind service in booking.

ASSISTANT: Thank you for opting us.