Discounts and commission

Hi there 


Can you please let us know how the shortfall or discounted rate that booking.com put on our site gets paid ?? they have a inhouse 10% discount for guests , and say they will pick up the cost, but when does it pay across to the guesthouse , As we have no current discounts running on our system . 


Please confirm as we have 3 bookings for next week and all 3 discounted by 10%