For the following set of commands the Contour Plot does not appear to display:

h = Cos[(2 \[Pi] ((x)^2 + (y)^2)/(2*5*w))]^2

h1
u1 = ContourPlot[h1 == 1, {x, -15, +15}, {y, -15, +15}, 
   GridLines -> Automatic];
u2 = Graphics[{Red, Point[{7, 11}]}];
s4 = Show[{u1, u2}]

Plot3D[h1, {x, -15, +15}, {y, -15, +15}]

The complete NoteBook is attached. You insights are welcome.

I'm using Version 11.3

Regards, Edward