Brand new test The Sims 4 folder. No mods. No CC.
I made a new random sim. Made sure to uncheck hair growth in CAS because this is a test game and I wasn't interested in such details. Just wanted a plain uncomplicated Sim.
However hair growth keesp re-enabling itself. At first I thought it was an oversight on my part, but I've now edited my Sim in CAS twice and each time it re-enables itself.
I don't know when this started, but this is the first time I've had this problem. Maybe game update 1.116, July 1, 2025.
Edit By Crinrict: Added Tag to Title