Create a zero mean complex gaussian,but its mean and pseudocovariance are not zero

I create zero mean circularly symmetric complex gaussian according to this website: https://stackoverflow.com/questions/14089934/circularly-symmetric-gaussian-variables-using-matlab

however,when i verify whether it is zero mean circularly symmetric complex gaussian or not,i found that the mean and pseudocovariance of gaussian i create is not zero,so i want to ask where am i wrong ?

My code

%zero mean circularly symmetric complex gaussian
L=5
h_1=normrnd( 0,sqrt(0.1*(L^(-2.5))) ,[4,1])+1i*normrnd( 0,sqrt(0.1*(L^(-2.5))) ,[4,1])

%Verify whether the mean is zero or not
expected_value=mean(h_1)

%Verify whether the pseudocovariance is zero or not
pseudocovariance=mean(h_1'*h_1)

%Verify whether the cov( e^{jk} * h_1) is equal to cov( h_1) or not
origi = cov(h_1)
origi_expon=cov(exp(1i*4)*h_1)
differ=origi-origi_expon

My zero mean circularly symmetric complex gaussian is a 4 by 1 matrix