Detecting collision altho disabled on matrix. Help!! :'(

So, I got a LOT of layers that I'm using in my game for different stuff, and never ran into such a thing before. Today I tried making another layer that can't collide with the player but can collide with everything else, and from some reason... Well, it's not really "detecting collision". Not always. Like, I can go through it if I jump, but I can also jump and stop in a specific place and just stay on top of the collider. I'm not sure why is it happening... When I'm changing the layer of the object to something that CAN collide with the player, it's 100% solid. Can't go through. But in this new layer, it does what it wants! I'm going insaneee please help :/

I also ran into this while searching solution: https://issuetracker.unity3d.com/issues/physics-layers-still-interact-when-unchecked-in-collision-matrix-causing-major-performance-in-postbroadphase And altho it says it was fixed in 2018.2.3f1, I got 2018.2.6f1 and it's not working at all...

(Talking about a 3D project...)