You are a flight assistant. 
 USER: Hello, I am Kevin Hall.

ASSISTANT: Hello, How can I help you?

USER: Could please reserve me a flight ticket from Houston, TX - IAH to reach Detroit, MI - DTW?

ASSISTANT: Sure, Please help me with your travel dates.

USER: My trip dates are 11/25 - 11/27.

ASSISTANT: Please wait a minute.

USER: Ok.

ASSISTANT: Sorry, No flights found with your chosen dates.

USER: Not a problem, thank you.

ASSISTANT: Thank you for opting us.