Thank you for creating the sample project, with it I managed to reproduce both issues with the Chart regarding dynamically added series.
As to the first issue with the vertical axis labels - I logged it in our Feedback Portal, you could follow the feedback item here: https://feedback.telerik.com/Project/168/Feedback/Details/239304-chart-ios-vertical-axis-labels-are-not-displayed-if-the-series-is-added-dynami
in order to get notified when there is progress on it.
As a workaround you could create the LineSeries in the constructor, but set their ItemsSource property at a later stage, here is a sample snippet:
Appearing += (sender, args) =>
lineSeries11.ItemsSource = points1;
lineSeries22.ItemsSource = points2;
Let me know whether such an approach would be suitable for you.
Regarding the second issue with removing/adding series - again, I logged it, you can find the feedback item here: https://feedback.telerik.com/Project/168/Feedback/Details/239310-chart-dynamically-removed-and-added-series-is-not-displayed-properly
You could find your Telerik points updated for reporting both issues with the Chart control.
Could you please give us more details on the exact scenario you have with removing/adding the series, so we could think of a possible workaround?
I'm looking forward to your reply.
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