You can try adding the series in the same order as the first time. This should paint all series with the same colors as the first time. If this does not help, you can bind the color of each series to a property exposed by your view model. To do so you can create a style targeting the corresponding series. In that style you will be able to use the property that controls the look of the series to bind it to your ViewModel.
To find out which properties among the series control their appearance, you can take a look at this article
Please give this approach a try and let me know if you need any further assistance.
Pavel R. Pavlov
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