Unable to remove spacing between columns



I am attempting to remove spacing between bars in a column chart using the following:

    [xAxis.style setInterSeriesPadding:@0.0];
    [xAxis.style setInterSeriesSetPadding:@0.0];

Now the spacing is reduced, but not removed.  There is still spacing between the columns.  As shown here.  How to solve that???

I have one column for every point on the X axis.  But I get this random different sized spaces. No idea why.