Recently,i am coding but i meet the problem

Cannot perform the operation: {real affine} ./ {real affine}

here is my code,i dont know where is wrong,i am very confused

clear all;

clc;

B = 20 ;

L = 150;

p = 100 ;

sigma = sqrt(10*10^-14)*10^3;

b = 5 ; % xita n =5

d = 1 ; %yita n =1

derta = 2 ; %derta n =2

N = 2; %2small cell

Kn = 2; %2small cell 2 users

e = zeros(N,Kn);

e_ele = log2(1+p/sigma);

e = e+e_ele;

fai = b * B * e_ele - derta * B - d *B * e_ele;

cvx_begin

variable a(2,2) nonnegative %a

variable s(2,2) nonnegative %s

expression y;

y=0;

for j=1:2

for i=1:2

y=y+a(i,j).*log( (s(i,j)*fai) /(a(i,j)+eps) );

end

end

maximize(y)

subject to

%% 1

s(1,1) + s(2,1) <= 1;

s(1,2) + s(2,2) <= 1;

%% 2

(s(1,1) + s(2,1)) * B * e_ele <= L;

(s(1,2) + s(2,2)) * B * e_ele <= L;

%% 3

a(1,1) >= s(1,1);

a(2,1) >= s(2,1);

a(1,2) >= s(1,2);

a(2,2) >= s(2,2);

%%

for i = 1:2

for j= 1:2

0<=a(i,j)<=1

0<=s(i,j)<=1

end

end

cvx_end