How to troubleshoot max7219?

[system]

You might have the polarity around the wrong way. With no more detail (like schematics) the rest is guesswork.

I have "crisped" one that way and there are no second chances, Maxim did not put polarity protection in. If you are lucky it will flicker nonsense. As CrossRoads stated, post the diagram of schematics. He and Nick are kinda sharp.