Occupancy pricing gives you a possibility to set up different prices for a different number of guests in your private rooms. In order to activate occupancy prices for your Booking Engine:
Make sure that the prices are set up correctly for each occupancy, see the instruction: How to set occupancy prices
Enable occupancy prices for Booking Engine, you can find that option in Property Settings / Booking Engine / Settings, right above the active room types list:
Check how the occupancy prices look like on your Booking Engine.