Refund on poor property ***

I booked on the 5th and 7th through booking.com at wavecrest 1205 in Durban On the 21st I got there the place is in a condition which you can not stay I can not believe booking.com post this on there app. The geyser is leaking whole ceiling full of mould and wet ,kitchen cupboard rusted and the window banks got wet brown marks. I phoned a couple of times wasted alot of airtime aswell. There feedback to me is if the property owner does not reply to there email they can not do anything for me . So the property owner never going to reply because they know not to and I never get anything back.How many people have they ****med like this? I did receive 15% back to say sorry but that is unacceptable I want my money . This is not a fault by my side but by them