Re: falcon on 22lr
Take the scope off the rifle. Put the scope on a level surface (table will do) such that the scope base only is touching the table. Make a mark on the wall about 10 yards away at a height equal to the lens center. Turn the elevation knob to half way between minimum and maximum. Look through the scope at the mark on the wall. The crosshair should be very near, if not exactly, on your mark.
If it is way off, in your case the scope may be well below the mark, the scope is bad. If it right on the scope is fine and you should look closely at how the scope is mounted to the receiver.