Most Apple Watch bands do this. My dad has a black Apple Watch band and it was exactly like you said and the matte soft finish was all shiny with sweat. I gave it a clean with water and cif and with a bit of elbow grease and it looks and feels brand new. I do this with all my bands when they get all sticky and gros. Hope this helps! 😄I think I’ll contact Apple, easily half the band is getting a shiny molted look. This is not the quality I paid for.