I bought my first pinball machine earlier today- The Shadow that I got an awesome deal on- and since bringing it home I noticed the ball lock "Sanctum" has not been working. I will hit the ball in the Sanctum area but the magnet appears to not be working. It still registers as a lock shot but it doesn't hold the ball. Is there something I should look for as a quick fix? I'm excited to work on this thing and make it immaculate and this is the only major issue that I've noticed so far that I need to fix. I tried to research the issue already but to no avail.