Shocking lack of service by Booking.Com

My son is doing a degree through Stellenbosch University but lectures are all being online (covid).He was notified that he had to go to Stellenbosch to do a particular test.I then made a reservation on Booking.Com only for my son to be advised an hour later that the test will now also be online.I therefore cancelled the booking on Booking.com only to be advised that the booking had been cancelled,however,I would NOT be refunded one cent of the payment made only an hour back. I am sure the accommodation had not even been advised of the booking.I emailed the accommodation explaining the situation & was told it was ‘out of their hands’.It is listed as ‘stunning flat in Jonkershoek,Lanzerac road) This despicable service will ensure I never use them ever again.I also suggest any potential clients are aware of this lack of service.