Hi,
You have retagged the buildings https://www.openstreetmap.org/way/291647969 and https://www.openstreetmap.org/way/291648351 to leisure=horse_riding (horse riding centres). Therefore they are no longer rendered like buildings. This was probably not intended. All buildings should have a building=* tag. If these buildings are indoor arenas you can tag them building=riding_hall INSTEAD OF leisure=horse_riding. The tag leisure=horse_riding is not for buildings, it is for complete riding centres (https://www.openstreetmap.org/node/2951129540 is ok).
See also:
https://wiki.openstreetmap.org/wiki/Tag:building=riding_hall
https://wiki.openstreetmap.org/wiki/Tag:leisure=horse_riding#When_not_to_use