It seems like this question was already answered in a support ticket you opened on the same question.
For anyone interested in this topic, below is the reply from the ticket:
"You can control DataPointLabels visibility with BarSeries -> DataPointStyle -> Visible property.
More details about configuring Graph's series are available in Formatting Graph Series help article.
Please check if you set any conditional formatting rules to hide specific data point labels."
If the issue still occurs, please attach a sample project reproducing it in a support ticket.
Do you want to have your say when we set our development plans? Do you want to know when a feature you care about is added or when a bug fixed? Explore the Telerik Feedback Portal
and vote to affect the priority of the items