You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: Can you please help me to book a flight ticket from LAS to IAH?

ASSISTANT: Sure, please share your preferred travel dates?

USER: My travelling dates are Sept 24 to Sept 26.

ASSISTANT: Let me know your other requirements?

USER: I want to return in the afternoon.

ASSISTANT: Can I have your name please?

USER: My name is Samantha Walker.

ASSISTANT: Do you have any class preference?

USER: I would like to prefer business class.

ASSISTANT: sorry, no flights found with your given details.

USER: No problem, thanks for your information.

ASSISTANT: Thank you for reaching us.