How do I plot an empty circle with no values in the middle of meshgrid plot3

Hi everyone.

Bascially I am tracking the depth of a surface using grids. x,y coordinates and z for depth. To fill the voids in between grids, I am using meshgrid with natural interpolation. However I have placed a circular piece in the middle of the grid hence on a plot3 it is supposed to be a white circular figue. How do I make sure this is drawn correctly because the image I attached does not look correct. Also how do I make sure that the meshgrid interpolates around the shape of the circle in the middle? This the code I have currently.

x = data(:,1); y = data(:,2); z = data(:,3)
x = table2array(x); y = table2array(y); z = table2array(z)
xlin = linspace(min(x), max(x), 100);
ylin = linspace(min(y), max(y), 100);
[X,Y] = meshgrid(xlin, ylin);
Z = griddata(x,y,z,X,Y,'natural');
% Z = griddata(x,y,z,X,Y,'cubic');
% Z = griddata(x,y,z,X,Y,'v4');
mesh(X,Y,Z)
axis tight; hold on
plot3(x,y,z,'.','MarkerSize',15)