It's not that uncommon for newly installed tiled floors to suffer from grout haze. This occurs where builder or tiler fails to remove all the excess grout from the surface of the tile after installation. It's not always immediately obvious as the grout has to dry before it shows up and if the tiles are sealed afterward the grout is trapped on the surface of the tile under the sealer which makes it even more difficult to remove. Not too long ago, I was called to address this exact problem
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