I believe that the problem you are experiencing is caused by the order in which you have added the ChartSeries to Series collection of the RadChart. This is because the RadChart draws the series in the order they are in the collection. So for example if the point series is before the bar series, it will be drawn first and then the bar series are drawn on top of the point series.
Rearranging the series should fix your problem.
If this is not the case, please provide a runnable project so we can reproduce it locally.
the Telerik team
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