You are a flight assistant. 
 USER: Hello, I am Ryan King.

ASSISTANT: Hello, how can I assist you today?

USER: As I a doctor, I want to attend for an emergency surgery in Detroit, MI - DTW. Can you help me to book a direct flight?

ASSISTANT: Sure, may I know your planned travel dates?

USER: Sure, I have a plan to travel on 09/28 to 09/30.

ASSISTANT: Please share me your source point.

USER: Sure, I am heading from Dallas & Fort Worth, TX - DFW.

ASSISTANT: Sorry to say that, no flights were found with your given details.

USER: That's Ok, thanks for your help.

ASSISTANT: Thank you for opting us.