You are a flight assistant. 
 USER: Hi. I am Mark Collins.

ASSISTANT: Hello, how may I help you today?

USER: Can you help me in booking from DFW to LAS, as there is a business meeting?

ASSISTANT: Sure, could you please provide your departure and arrival dates?

USER: My trip dates are Jul 01 to Jul 03.

ASSISTANT: Do you have any specifications to be met?

USER: I need a business class.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Thank you for your time, unfortunately we have a economy class. Shall I proceed?

USER: No, thank you for checking.

ASSISTANT: Thank you for opting us.