Macbook charge not stopping at 80% when optimized

It's been a few months since I've been trying to activate the feature "Optimize battery charging" for my MacBook Air M1 (I have the latest MacOS 12.4), but even though it's supposedly activated, the charge never stops at 80%, and always goes to 100%. I'm trying to use this feature to protect my battery health, but nothing seems to work. I've already de-activated and re-activated it many times. Does anyone have the same issue? Any suggestions? Thank you.