Index exceed matrix Dimensions error

Hi friends, I have an optimization model that I am going to get the optimal answer with the genetic algorithm, one of our cost semesters is as follows:

Cost of transporting packs from warehouses to tents: ∑∑∑ 𝐶𝐵(n, j, k) 𝑃𝐵(n, j, k). Which I wrote in MATLAB as follows :

pop(it,np).cost.term3=0;
 for n=1:N
 for j=1:J
 for k=1:K
pop(it,np).cost.term3=pop(it,np).cost.term3+pop(it,np).arthvar.PB(n,j,k). *CB(n,j,k); 
 end
 end
 end

Now the problem is that MATLAB gives this error. While the dimensions of the matrix are the same and when I turn.* to * again, it gives an error, while when I copy my matrix in the Command Window and execute this loop, it resolves without any error while it is not in the code.

[Walter Roberson]

At the command window command

dbstop if error

when it stops, ask

[it, np, n, j, k]
size(pop)
size(pop(it,np).arthvar.PB)
size(CB)