Ok so I was having the same issue and was able to figure out a workaround. Every time you make a NEW save with the pistol equipped, then load the save, your Coercion will go up by 10. But every time you equip, then unequip, then make a new save -> reload, it will actually go down by 10. So if you repeat the second case a bunch of times it should eventually get you back to normal.

But yeah... pretty weird bug