Painting Tool Not Painting Surfaces (stays with the tiled pattern)

I am trying to make a new map, and after creating the landscape with the correct materials, I go to paint it all the beach texture to start. But when i select the beach texture on the Paint tab, and assign the LayerInfo file, when i go to paint the ground it doesn’t change. Also, in the small box preview pictures (shown in the image) there is no colour to the balls which from tutorials should have it.