White boxes in the legend

Hello, I'm a beginner with Matlab and I need some help with this code. The problem is the legend, as you can see in the jpeg(the white boxes). In this case I used only two files but the result is the same with more files. Can you help me, please?

for j=1:numel(files)

  %% I set a,b,c this way because I want to change the color form blue to red, whatever it is the number of files  
   a=(1/numel(files))*j;                                                              
   b=((8/(numel(files)^2))-(12/(numel(files))^2))*(j^2)+(4/numel(files))*j;
   c=1-a;

    figure(4);
   
    subplot(2,2,1); 
    sphere; h = findobj('Type','surface'); 
    axis equal;
    hold on;
   
%%%% Add the point due to my analysis
    scatter3(X_ps,Y_ps,Z_ps,sz,'MarkerEdgeColor',[a b c],...
        'MarkerFaceColor',[a b c]); view(0,90)
   
    subplot(2,2,2) 
    sphere; h = findobj('Type','surface'); 
    axis equal;
    hold on;
   
 scatter3(X_ps,Y_ps,Z_ps,sz,'MarkerEdgeColor',[a b c],...
        'MarkerFaceColor',[a b c]); view(0,0)
   
subplot(2,2,3) 
    sphere; h = findobj('Type','surface'); 
    axis equal;
    set(h, 'FaceColor','none','EdgeColor',[.7,.7,.7]);
    hold on;

    scatter3(X_ps,Y_ps,Z_ps,sz,'MarkerEdgeColor',[a b c],...
        'MarkerFaceColor',[a b c]); view(90,0)
    hold on;
    
end

%%%% Legend display 
    
legend('T=4K','T=25K','T=50K','T=75K','T=100K','T=125K','T=150K');  
newPosition = [0.6 0.2 0.2 0.2];
    set(legend,'Position', newPosition);