You likely polished some sections of the matte decal and I'm not entirely sure you can get it back 100% to matte. Ask me how I know. I ended up removing the center matte decal on mine and was going to pay to have the dealer replace it but actually liked the look without it, not to mention being free of the special attention needed for a Matte decal. I can just buff and polish without any worries or dealing with water spots, etc.
Also imho the decal was too close to the nightfall gray and didn't really add much.
