Im a bit confused firstly what Game is it?  And when you say its missing a ball after a game so it plays fine then once youve finished it doesnt start again or comes up with an error?

Sorry, will give more info.

It's The Shadow. The game plays fine, but once it ends, it won't start again and says there's a pinball missing.
It tries to clear it, but that doesn't work. I've found the only way to play another game is to turn the power off
and on again. Also on some occasions it will have a dot after "Free Play.", which i've been told is another error. It's
just annoying having to turn it on and off again to play a new game.