Class Activation Map, Classify requires at least 3 arguments for (.h5 CNN model)

I have an error related to classify function ;

I tried to read its documentation, Do you think the problem with our model has no categorical classes for the group argument? or matlab invokes stat classify instead of DL classify?

It works fine with other nets like googlenet .

net = importKerasLayers("best_model.h5", 'ImportWeights', true);

img = imread("normal.PNG");

img = rgb2gray(img);

img = imresize(img, [240,120]);

[classfn,score] = classify(net,img);

imshow(img);

title(sprintf("%s (%.2f)", classfn, score(classfn)));

map = gradCAM(net,img,classfn);

imshow(img);

hold on;

imagesc(map,'AlphaData',0.5);

colormap jet

hold off;

title("Grad-CAM");

Error using classify (line 123)

Requires at least three arguments.

Error in CAMtrial (line 9)

[classfn,score] = classify(net,img);

Thanks ;

Omar