When you tighten the chip breaker screw, it can flex the chip breaker enough to open a small gap between the front of the chip breaker and the blade. The easiest way to fix it is to lay the front quarter inch or so of the chip breaker on your stone and the back end on the bench that is supporting the stone, with the surface that meets the blade down against the stone. This preferentially removes metal from the back edge of the mating surface. Then simply hone the chip breaker back and forth until the mating surface is flat. Use a Sharpie marker if necessary to indicate when you have achieved flat.
Since I'm not near my shop and camera right now, I found an image on the web that is illustrative: