From the Edition section of the action bar, click Control Points .
The Control Points dialog box
appears.
Select Surface.1.
Select the control point as shown.
Click Smooth
You can adjust the smoothing factor slider to
fit your needs. The greater the smoothing factor value is the smoother the
result will be.
The surface has been smoothed according to the selected control point.
Click OK to validate modifications and close
the dialog box.