How to modify a 2d array [,] of a class?

I have a Class that looks like:

public class ProcessorSlotDetails {
	public GameObject button;

	public string slotType;
	public int testInt;
	public int[] positiveOutDirection;
	public int[] negitiveOutDirection;
	public int[,] enterDirections;

}

public class ProcessorDetails {
	public int processorColumnsSlots;
	public int processorRowSlots;

	public ProcessorSlotDetails[,] processorSlotDetails;
}

and I am trying to addess variable inside but I can’t figure out what will work:

 processorDetails.processorSlotDetails[1,1].slotType = "new";
 //or
 processorDetails.processorSlotDetails.slotType.SetValue( "new", 1,1)

Any Idea what I an doing wrong?

Thanks!

This might help: