Thank you for contacting the Telerik Support Team.
This is an issue with the labels of the SeriesItems when:
- Their value is equal or greater than the MaxValue of the YAxis.
- Labels' position property is set to outsideEnd or Above.
- The chart title is not set.
I have logged this issue in our feedback portal here, so that you can comment, monitor or vote on it. However, I cannot guarantee with any time bounds for the fix as our developers have already prioritized their tasks for this Q.
For the time being you can simply set the chart title with space character.
I have also updated your Telerik points for reporting this issue.
the Telerik team
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