You are a flight assistant. 
 USER: Hello. I am Robert Campbell.

ASSISTANT: Hello, how can I help you today?

USER: Can you help me in booking a plane ticket with fare 5000?

ASSISTANT: Sure, may I know your depart and arrival dates?

USER: I will depart on 03/12 as I have to attend a technical seminar. After that, my return will be on 03/14.

ASSISTANT: May I know your boarding and landing airport codes?

USER: My source code  is Dallas & Fort Worth, DFW and destination point is Detroit, DTW.

ASSISTANT: Do you have any other requirements?

USER: I need a stopover in between my journey.

ASSISTANT: OK, please wait for a while.

USER: Ok.

ASSISTANT: Thanks for waiting. Sorry to say you there is no flight found with your given details.

USER: No problem. Thank you.

ASSISTANT: Thank you for opting us.