Your nock point should never be below square on a bow that's set up correctly. Might be your tiller needs adjustment. Check the measurement from the base of the limbs to the string at each end of the bow's riser. If it checks the same, then you need to move your nock point. If the measurements are different, especially if the top limb measures closer to the string than the bottom, you need to adjust the limb bolts till they check the same. Then reset your nock point.

To start out, I usually set my nock point so that the nock end of the arrow is about 1/16" - 1/8" higher than the point, depending on whether I'm shooting release or fingers, making sure the arrow shaft is centered on the rest mounting hole in the riser. That's your starting point for getting the bow tuned. I make adjustments from there, to the bow's tiller to get the best feel and performance, and to the nock point to get my best arrow flight.