As I understand your question - you are asking how to rotate the chart label to display vertically.
You can rotate the X axis label as follows:
chart1.ChartAreas[0].AxisX.LabelStyle.Angle = -90;
It is assumed that you linked your series to the first area of ββthe chart, which by default does not change when using the Winforms constructor.
The following figures show how the diagram will look before the code above is applied, the second image shows how it appears after applying the code.
Let me know if this is not what you are trying to do and I will post an updated answer.
Before the turn

After turning

Edit: another answer added after posts were mentioned in my previous posts, it may be important to set chartArea1.AxisX.IsLabelAutoFit = false;
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