I have error in equation "B", please can you help me to know what is the problem? "Semantic Segmentation"

Hi,

I am training to run this tutorial in MATLAB:

"Semantic Segmentation of Multispectral Images Using Deep Learning"

https://www.mathworks.com/help/images/multispectral-semantic-segmentation-using-deep-learning.html

I have error in equation "B", please can you help me to know what is the problem?

>> B = labeloverlay(histeq(train_data(:,:,4:6)),train_labels,'Transparency',0.8,'Colormap',cmap);

Error using labeloverlay>parseInputs (line 174)

Size of input image matrices must agree.

Error in labeloverlay (line 87)

parsedInputs = parseInputs(varargin{:});

[darova]

train_data(:,:,4:6)) - you choose only 3 elements

train_labels - how many elements here?