So I recently found a thing with some custom hairs.
As you can see, the hair has discoloured, almost washed away looking pieces. (The hair I used is Daya Dreads by SavvySweet). However, if I open up the hair in sims 4 studio, it appears normal like this: When I exported the mesh, I saw that the uv_1 wasn't properly made. It was all in one litle piece at the bottom left except for the uv for the bun which was lighter in game.
Without making a proper unwrap for the hair, I only moved the piece up to the same height as the bun on the uv map.
When I imported the mesh like this and started up the game, it looked like this: I'm not sure if someone else has already documented this, but I couldn't find anybody who knew about this. I hope you found this helpful!
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