Could anyone help me to overcome the error

clear all
clc
%-----Simulation Parameters-----%
Bmax=2000000; %maximum available bandwidth for OFDMA
noise=1e-9; %fixed noise power is assumed
p_fix=0.01; %fixed transmit power is assumed
N_UE=[2 4 6 8 10];
N_SC=[12 14 16 18 20];
for it=1:2
for t= 1:length(N_UE)
     %-----Topology-----%
    Xmax=1; % x-coordinate for base station
    Ymax=1; % y-coordinate for base station
    radius=5; %coverage radius
    xsd=ones(1,N_UE(t))*Xmax;
    ysd=ones(1,N_UE(t))*Ymax;
    rrx=radius*sqrt(rand(1,N_UE(t)));
    thetarx=2*pi*rand(1,N_UE(t));
    ang=0:0.01:2*pi;
    xrx=xsd+rrx.*cos(thetarx); %random position of receivers-->x-coordinate
    yrx=ysd+rrx.*sin(thetarx); %random position of receivers-->x-coordinate
    th = 0:pi/100:2*pi;
    xunit = radius * cos(th) + Xmax;
    yunit = radius * sin(th) + Ymax;
%     figure
%     plot(xunit, yunit);
%     hold on
%     plot(ysd,xsd,'r^')
%     hold on
%     plot(yrx,xrx,'ko')
%     hold on
    %-----Subcarrier Correlation Matrix-----%
    ratio=0.1; %Td over Tb: delay spread relative to OFDM frame duration
    c=2*pi*ratio;
       for r = 1:length(N_SC)
         for j=1:N_UE(t)
            temp=[];
            for n=1:N_SC(r)
                nc=(n-1)*c;
                entry=(1+i*nc)/(1+nc^2);
                temp=[temp entry];
            end
            Rchan=toeplitz(temp);
            %autocorrelation matrix
            [E,L]=eig(Rchan);
            SQRTL=sqrt(L);
            A=E*SQRTL/sqrt(2);
            GG=randn(N_SC(r), 1)+i*randn(N_SC(r),1);
            H=A*GG;
            HH=abs(H);
%            figure
%            plot(abs(H))
%            hold on
            for k=1:N_SC(r)
                F(j,k)=HH(k);
            end
        end
       %-----Subcarrier Gain-----%
        as=4;
        bs=10;
        Lsigma=as+(bs-as)*rand(1,N_UE(t));
        Lshadow=10.^(randn(1,N_UE(t)).*(Lsigma/10));
        ae=3;
        be=5;
        Lexp=ae+(be-ae)*rand(1,N_UE(t));
        for k=1:N_SC(r)
            for j=1:N_UE(t)
                dist2(j)=sqrt((xrx(j)-xsd(j))^2+(yrx(j)-ysd(j))^2);
                G(j,k)=(F(j,k)*Lshadow(j))/dist2(j).^Lexp(j);
            end
        end
        %subcarrier allocation to users%
        siz = size(G);
        idx = sub2ind(siz, randi([1,N_UE(t)], 1, siz(2)), 1:siz(2));
        C = zeros(siz);
        C(idx) = G(idx);
        D=sum(C,2); 

% Throughput performance %
        throughput =((Bmax.*log(1+((p_fix).*C))./noise));
        overall_throughput = sum(sum(throughput));
        output(t,r)=overall_throughput;
        output_it(t,r,it)=output(t,r);
 %       figure
%         plot(overall_throughput,'b','linewidth',2);
%         legend(['No.of subcarriers=' num2str(N_SC(r))])
%         xlabel('No of users')
%         ylabel('overall_throughput')
%         axis square
%         grid on

      end
  end
  end

out = sum(output_it,3);
final = out./2;

%Group formation%
N_G=5;%No of group
B = cell(N_G,1);
sumB = cell(N_G,1);
for d=1:1:N_G
    if d==1
      e=randi([2 5],1)% select No of UE randomly  
    else
      sz=length(C(:,1));
    e=randi([1 sz],1)% select No of UE randomly   
    end
    idx=randsample(1:size(C,1),e)
    B{d} = C(idx,:)
    C(idx,:) = []
    [rows, columns] = size(B{d});
    % Get sum of columns and replicate vertically.
    sumB{d} = repmat(sum(B{d},1), [rows, 1])
end

E=[sumB{1}; sumB{2};sumB{3};sumB{4};sumB{5}]

If i run this code i am getting Error using randi First input must be a positive scalar integer value IMAX, or two integer values [IMIN IMAX] with IMIN less than or equal to IMAX.

Error in model (line 113) e=randi([1 sz],1)% select No of UE randomly.

could anyone help me to overcome this error.