BDC are not following their own advice. It looks unlikely you will get a refund from them if it is a non-refundable booking, even if a forced cancellation. I cancelled a non-refundable booking, contacted the accommodation owner who agreed to a full refund. She informed Booking.com using the accommodation owner's dashboard, but they did not honor this and will only offer me 15% refund. They now do not answer any messages. It's clear from their Facebook page there are many people in the same situation.