Reset Galaga Machine Controls.

So I was playing a Galaga machine and accidentally inserted a coin before entering name for high score. Entered name and went back to home screen. It’s says there’s one credit but when I hit start button, nothing happens. Inserted another coin and it says two credits, but buttons still don’t work. Anyone know what might have happened? Will unplugging it and plugging it back in solve the problem? Anyone know how to fix it?