Cancel reservation due to property damage and sale of property / why can't I contact booking.com

I have damage to my condo due to two hurricanes that have hit it (Sally / Zeta).  I've tried unsuccessfully to contact the customer by phone and by email and they will not respond.  I have also tried unsuccessfully to just try and find a way to contact booking.com which apparently is completely impossible.

How do I address canceling the reservation - and removing my ALL of my properties from this platform....