label are not visible in chart

foreach (DataRow dr in dts.Rows)
                          {
                             series.Points.AddXY(dr["outcome"].ToString(), dr[i]);
                          }
                           series.Name = dts.Columns[i].ToString();
                           series.ChartArea = "area";
                           series.Legend = "leg1";
                           chart_.Series.Add(series);
                           chart_.ChartAreas[0].AxisX.IsLabelAutoFit = true;
                           chart_.ChartAreas[0].AxisX.LabelStyle.Angle = -90;