Griddata is omitting boundary data

I am trying to plot 3d mesh plot using grid data. I have imported x,y, z cordinate data from .txt file. I am unable to fiugure out why grid data is omiting data on corner. See the image attached. I plotted 3d scttered data using plot3 comand to ensure there exist data, which is denoted by circles. I have 403 nodes and its x,y,z coordinates.

my programme is as follows.

x=disp(:,1); %x-cordinates of data point
y=disp(:,2); %y-cordinates of data point
z=disp(:,3); %z-cordinates of data point

[xq,yq]=ndgrid(0:0.01:0.3, 0:0.005:0.06);%mesh grid 
vq= griddata(x,y,z,xq,yq);
figure
mesh(xq,yq,vq);
hold on;
plot3(x,y,z,'o');

[Walter Roberson]

difficult to say without the data .

[Abhijeet Marekar]

My professor helped me with the problem. Matrix generated by ''griddata'' had 'NaN' values at some boundary points. These bounday points were outside of convex hull of griddata. I used ''scatteredInterpolant'' to extrapolate data and it worked.

m=0:0.01:0.3;
n=0:0.005:0.06;
[xq,yq] = ndgrid(x,y);
F = scatteredInterpolant(x,y,z,'nearest');
[a,b] = ndgrid(m,n);
vq = F(a,b);
figure
surf(a,b,vq);

@Walter Roberson thank you for your attention..!!