Error in Contour Plotting

I am trying to plot a contour plot with the data exported from some other simulator. I have written the following code but on execution I am getting an error. I am also including the data set file from where I am trying to create the contour plot.

Code:

clear all
close all
clc
load('v_f_100nm_0_00.mat');

x2 = linspace(min(charge.x),max(charge.x),436); 
z2 = linspace(min(charge.z),max(charge.z),436);

[X,Z]  = meshgrid(charge.z,charge.x);      
[X2,Z2] = meshgrid(z2,x2);

n2 = interp2(X,Z,charge.n,X2,Z2);  

% transpose matrix
n3 = n2.';

imagesc(x2,z2,n3); 
colorbar;      
set(gca,'Xlim',[min(charge.x),max(charge.x)]); 
set(gca,'Ylim',[min(charge.z),max(charge.z)]); 
set(gca,'YDir','normal');

Error Information:

Error using griddedInterpolant
The number of input coordinate arrays does not equal the number of dimensions (NDIMS) of these arrays.

Error in interp2>makegriddedinterp (line 228)
    F = griddedInterpolant(varargin{:});

Error in interp2 (line 136)
        F = makegriddedinterp(X, Y, V, method,extrap);

Error in matlab_code_charge_polt (line 18)
n2 = interp2(X,Z,charge.n,X2,Z2);

Kindly help to resolve the issue. Actually I am not getting the error caused by the command, "interp2".