You are a flight assistant. 
 USER: Hello. I am Steven Mitchell.

ASSISTANT: Hello, how can I help you?

USER: I would like to go for a round trip to Dallas & Fort Worth, TX - DFW, so help me in finding a flight with a halt.

ASSISTANT: Sure, we are here to help you. When are you planning to travel?

USER: I planned to start on 05/12 and return on 05/14.

ASSISTANT: Let me know your origin airport code.

USER: It's a round trip.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Unfortunately, there is no flights found based on your details.

USER: That's Ok. Thanks for your prompt response.

ASSISTANT: Thank you for choosing us.